Re: [MBZ] 300 ACC Issue
I tried tightening the valve and it was already tight. I guess it may be the seal in it. They are a very tiny little seal. So the next time it goes down I'll try to get it out an go from there. I like the idea of mineral oil myself but had to put in the other stuff because I changed to the 134a back when. To go back I would have to clean and flush everything and put a new dryer on. May do that when the time comes. I don't know about the not into a vacuum. Didn't make sense to me either, not what I learned long ago but since there was a bit of residual still in there I just went with it and it seems to work. So far. Manfred Date: Sat, 17 Mar 2012 06:17:20 -0800 From: Jim Cathey j...@windwireless.net Subject: Re: [MBZ] 300 ACC Issue The leak seems to be at the fill valve These are Schrader valves, I've had loose ones that I've tightened with a standard tire tool, 'live'. done that before but they don't seem to last very long. Nasty refrigerant/oils eating the seal? I sure like mineral oil and HC's! They do say not to put the stuff into a vacuum Whyever not? That's SOP for A/C work. What are you _supposed_ to do with it after a full servicing? -- Jim ___ http://www.okiebenz.com For new and used parts go to www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
Re: [MBZ] 300 ACC Issue
I ordered new schrader valve cores from Mr. Q for my 87 300D last year. Took care of the leaks. I tried tightening the valve and it was already tight. I guess it may be the seal in it. They are a very tiny little seal. So the next time it goes down I'll try to get it out an go from there. I like the idea of mineral oil myself but had to put in the other stuff because I changed to the 134a back when. To go back I would have to clean and flush everything and put a new dryer on. May do that when the time comes. I don't know about the not into a vacuum. Didn't make sense to me either, not what I learned long ago but since there was a bit of residual still in there I just went with it and it seems to work. So far. Manfred Date: Sat, 17 Mar 2012 06:17:20 -0800 From: Jim Cathey j...@windwireless.net Subject: Re: [MBZ] 300 ACC Issue The leak seems to be at the fill valve These are Schrader valves, I've had loose ones that I've tightened with a standard tire tool, 'live'. done that before but they don't seem to last very long. Nasty refrigerant/oils eating the seal? I sure like mineral oil and HC's! They do say not to put the stuff into a vacuum Whyever not? That's SOP for A/C work. What are you _supposed_ to do with it after a full servicing? -- Jim ___ http://www.okiebenz.com For new and used parts go to www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com ___ http://www.okiebenz.com For new and used parts go to www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
Re: [MBZ] 300 ACC Issue
Yup and no having to look around for the components or how to get them into the system. Works great and easy to put in. Works for me. Mind you cheaper would be better but Manfred Date: Fri, 16 Mar 2012 19:49:37 -0400 From: Allan Streib str...@cs.indiana.edu Subject: Re: [MBZ] 300 ACC Issue Envirosafe is a hyrdrocarbon blend with a scent. Basically just propane/isobutane. -- 1983 300D 1979 300SD ___ http://www.okiebenz.com For new and used parts go to www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
Re: [MBZ] 300 ACC Issue
From what I remember reading on their web site you can use any oil and even mix and match the various refrigerants. In my case I had been using 134a and had the ester oil in there. There was enough in there to have about 5lbs pressure. I just shook the can and then inverted the can and ran it in like it said. I actually put in one can last year with the 134a to get the system up to cooling right near the end of the summer and it worked just the same as the 134a alone. Over the winter most of everything leaked out so now I have pretty much just the envirosafe in it. The leak seems to be at the fill valve so not having any way to recover the stuff I guess I will just have to wait till it leaks out again and then replace the valve. I seem to remember having done that before but they don't seem to last very long. They do say not to put the stuff into a vacuum so maybe you will have to put just enough 134a in there to get about 5lbs and then go from there. Two cans was just right for mine so you probably don't need any more then that. If you want to come over some time I have some extra so we can put that in right quick. Manfred Date: Fri, 16 Mar 2012 23:25:22 -0400 From: Gerry Archer arche...@embarqmail.com Subject: Re: [MBZ] 300 ACC Issue Hi Manfred, Do you have ester oil in your A/C system or did you flush and change it? I'm thinking of putting Envirosafe in one of mine but wondered if oil had to be changed since I just flushed the system and put in fresh ester oil, a new compressor. and a new filter unit. I have a good vacuum pump. Thanks, Gerry P.S. I have a couple of the ram chips out of a no-name laptop that you can have if the 512s don't work. Contact me offline if you need them. ___ http://www.okiebenz.com For new and used parts go to www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
Re: [MBZ] 300 ACC Issue
The leak seems to be at the fill valve These are Schrader valves, I've had loose ones that I've tightened with a standard tire tool, 'live'. done that before but they don't seem to last very long. Nasty refrigerant/oils eating the seal? I sure like mineral oil and HC's! They do say not to put the stuff into a vacuum Whyever not? That's SOP for A/C work. What are you _supposed_ to do with it after a full servicing? -- Jim ___ http://www.okiebenz.com For new and used parts go to www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
Re: [MBZ] 300 ACC Issue
Thanks, Manfred, I'll contact you next time I'm going up that way and bring along the ram just in case. Gerry From: MG trainpain2...@yahoo.com From what I remember reading on their web site you can use any oil and even mix and match the various refrigerants. In my case I had been using 134a and had the ester oil in there. There was enough in there to have about 5lbs pressure. I just shook the can and then inverted the can and ran it in like it said. I actually put in one can last year with the 134a to get the system up to cooling right near the end of the summer and it worked just the same as the 134a alone. Over the winter most of everything leaked out so now I have pretty much just the envirosafe in it. The leak seems to be at the fill valve so not having any way to recover the stuff I guess I will just have to wait till it leaks out again and then replace the valve. I seem to remember having done that before but they don't seem to last very long. They do say not to put the stuff into a vacuum so maybe you will have to put just enough 134a in there to get about 5lbs and then go from there. Two cans was just right for mine so you probably don't need any more then that. If you want to come over some time I have some extra so we can put that in right quick. Manfred Date: Fri, 16 Mar 2012 23:25:22 -0400 From: Gerry Archer arche...@embarqmail.com Subject: Re: [MBZ] 300 ACC Issue Hi Manfred, Do you have ester oil in your A/C system or did you flush and change it? I'm thinking of putting Envirosafe in one of mine but wondered if oil had to be changed since I just flushed the system and put in fresh ester oil, a new compressor. and a new filter unit. I have a good vacuum pump. Thanks, Gerry P.S. I have a couple of the ram chips out of a no-name laptop that you can have if the 512s don't work. Contact me offline if you need them. ___ http://www.okiebenz.com For new and used parts go to www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com - No virus found in this message. Checked by AVG - www.avg.com Version: 10.0.1424 / Virus Database: 2113/4876 - Release Date: 03/17/12 ___ http://www.okiebenz.com For new and used parts go to www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
Re: [MBZ] 300 ACC Issue
Tests this morning would indicate that the compressor clutch is open circuited. Ohmmeter readings are open and applying B+ directly to the connector at the compressor yield no response. Sigh. I can't see attempting to replace the clutch in car since I don't have all the required tools. What kind of a job is replacing the compressor on this beast like? It's really stuck in there, but I'm just looking at it from the top. Also, this is currently an R12 system. I really don't want to convert it, as R134a in these systems just doesn't cut it in this climate. I have one can of R12, which I am sure will not be enough to charge the system. Can I go with propane and not have to hassle with purging the system and all that? Suggestions are welcome. I have not yet convinced myself that I want to do this, but I don't have any trusted auto AC people around here to work with, either... Thanks, Dan ___ http://www.okiebenz.com For new and used parts go to www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
Re: [MBZ] 300 ACC Issue
I'll try to find and send the pdf if you want. I've kept both of mine R-12; I've been getting the 12 oz. cans from somebody I found on internet (well, actually, local refer guy gets 'em for me from guy I found) @ about $27/can, I think. BTW, didn't I get that stuff years ago for 'bout 50 to 75 cents/can? I also saw 10-cent fuel (#2) @ $4.05/gal. this morning. Wilton - Original Message - From: Dan Penoff lwb...@yahoo.com To: Mercedes Discussion List mercedes@okiebenz.com Sent: Friday, March 16, 2012 10:42 AM Subject: Re: [MBZ] 300 ACC Issue Tests this morning would indicate that the compressor clutch is open circuited. Ohmmeter readings are open and applying B+ directly to the connector at the compressor yield no response. Sigh. I can't see attempting to replace the clutch in car since I don't have all the required tools. What kind of a job is replacing the compressor on this beast like? It's really stuck in there, but I'm just looking at it from the top. Also, this is currently an R12 system. I really don't want to convert it, as R134a in these systems just doesn't cut it in this climate. I have one can of R12, which I am sure will not be enough to charge the system. Can I go with propane and not have to hassle with purging the system and all that? Suggestions are welcome. I have not yet convinced myself that I want to do this, but I don't have any trusted auto AC people around here to work with, either... Thanks, Dan ___ http://www.okiebenz.com For new and used parts go to www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com ___ http://www.okiebenz.com For new and used parts go to www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
Re: [MBZ] 300 ACC Issue
I checked Angie's List for some reputable auto AC places around here and set him out to get some estimates. I would really love to send him to a third generation MB shop (Ledbetters) who has forgotten more than any dealer will ever know - Rusty knows these guys and can vouch for them - there is no better than these guys. That being said, they would fix it right, meaning they would go completely through it and it would be as new. Only problem is that he would end up having more in repairs than the car is worth. We'll see what the locals say when he gets back. I told him to say nothing other than The AC doesn't work. Dan On Mar 16, 2012, at 2:50 PM, WILTON wilt...@nc.rr.com wrote: I'll try to find and send the pdf if you want. I've kept both of mine R-12; I've been getting the 12 oz. cans from somebody I found on internet (well, actually, local refer guy gets 'em for me from guy I found) @ about $27/can, I think. BTW, didn't I get that stuff years ago for 'bout 50 to 75 cents/can? I also saw 10-cent fuel (#2) @ $4.05/gal. this morning. Wilton - Original Message - From: Dan Penoff lwb...@yahoo.com To: Mercedes Discussion List mercedes@okiebenz.com Sent: Friday, March 16, 2012 10:42 AM Subject: Re: [MBZ] 300 ACC Issue Tests this morning would indicate that the compressor clutch is open circuited. Ohmmeter readings are open and applying B+ directly to the connector at the compressor yield no response. Sigh. I can't see attempting to replace the clutch in car since I don't have all the required tools. What kind of a job is replacing the compressor on this beast like? It's really stuck in there, but I'm just looking at it from the top. Also, this is currently an R12 system. I really don't want to convert it, as R134a in these systems just doesn't cut it in this climate. I have one can of R12, which I am sure will not be enough to charge the system. Can I go with propane and not have to hassle with purging the system and all that? Suggestions are welcome. I have not yet convinced myself that I want to do this, but I don't have any trusted auto AC people around here to work with, either... Thanks, Dan ___ http://www.okiebenz.com For new and used parts go to www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com ___ http://www.okiebenz.com For new and used parts go to www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com ___ http://www.okiebenz.com For new and used parts go to www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
Re: [MBZ] 300 ACC Issue
Just this morning I put two cans of envirosafe into my 123 AC system. It was all but empty so it was just the right amount. I am now getting 32 deg at the center vents going down the road. I had 134a in there before and was happy to get 40. I forget what I paid for the envirosafe but it wasn't anywhere near $27 a can. Look for it on the net. I'm sold on it. Manfred Date: Fri, 16 Mar 2012 10:42:47 -0400 From: Dan Penoff lwb...@yahoo.com Subject: Re: [MBZ] 300 ACC Issue Tests this morning would indicate that the compressor clutch is open circuited. Ohmmeter readings are open and applying B+ directly to the connector at the compressor yield no response. Sigh. I can't see attempting to replace the clutch in car since I don't have all the required tools. What kind of a job is replacing the compressor on this beast like? It's really stuck in there, but I'm just looking at it from the top. Also, this is currently an R12 system. I really don't want to convert it, as R134a in these systems just doesn't cut it in this climate. I have one can of R12, which I am sure will not be enough to charge the system. Can I go with propane and not have to hassle with purging the system and all that? Suggestions are welcome. I have not yet convinced myself that I want to do this, but I don't have any trusted auto AC people around here to work with, either... Thanks, Dan ___ http://www.okiebenz.com For new and used parts go to www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
Re: [MBZ] 300 ACC Issue
MG trainpain2...@yahoo.com writes: Just this morning I put two cans of envirosafe into my 123 AC system. It was all but empty so it was just the right amount. I am now getting 32 deg at the center vents going down the road. I had 134a in there before and was happy to get 40. I forget what I paid for the envirosafe but it wasn't anywhere near $27 a can. Look for it on the net. I'm sold on it. Envirosafe is a hyrdrocarbon blend with a scent. Basically just propane/isobutane. -- 1983 300D 1979 300SD ___ http://www.okiebenz.com For new and used parts go to www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
Re: [MBZ] 300 ACC Issue
I can't see attempting to replace the clutch in car since I don't have all the required tools. So far as I know there's only one special tool, and it's not too expensive if you find the right one. Less than cans of refrigerant! (I made my own, but wish I hadn't had to.) See: http://userweb.windwireless.net/~jimc/mb190dlog.html#clutchtool -- Jim ___ http://www.okiebenz.com For new and used parts go to www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
Re: [MBZ] 300 ACC Issue
That may be true, but in all honesty, I just don't have the time or desire to tear into this thing. If it as something a little less involved, fine, but otherwise I'll let the youngster find a rusted indy to sort it out and help him with the cost if necessary. Thanks to all who assisted. I have a much better understanding of the later AC systems now Dan On Mar 16, 2012, at 8:41 PM, Jim Cathey wrote: I can't see attempting to replace the clutch in car since I don't have all the required tools. So far as I know there's only one special tool, and it's not too expensive if you find the right one. Less than cans of refrigerant! (I made my own, but wish I hadn't had to.) See: http://userweb.windwireless.net/~jimc/mb190dlog.html#clutchtool -- Jim ___ http://www.okiebenz.com For new and used parts go to www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com ___ http://www.okiebenz.com For new and used parts go to www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
Re: [MBZ] 300 ACC Issue
I'll let the youngster find a rusted indy . Yes, Rusty's the best. Fred Moir Lynn MA Diesel preferred On 3/16/2012 9:00 PM, Dan Penoff wrote: That may be true, but in all honesty, I just don't have the time or desire to tear into this thing. If it as something a little less involved, fine,but otherwise I'll let the youngster find a rusted indy to sort it out and help him with the cost if necessary. Thanks to all who assisted. I have a much better understanding of the later AC systems now Dan ___ http://www.okiebenz.com For new and used parts go to www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
Re: [MBZ] 300 ACC Issue
Hey! Been out in the garage building drawers for the youngest's bureau. I'm tired and frustrated Chuckle. Dan hitting the showers and going to bed On Mar 16, 2012, at 9:13 PM, Fred Moir fred.s...@verizon.net wrote: I'll let the youngster find a rusted indy . Yes, Rusty's the best. Fred Moir Lynn MA Diesel preferred On 3/16/2012 9:00 PM, Dan Penoff wrote: That may be true, but in all honesty, I just don't have the time or desire to tear into this thing. If it as something a little less involved, fine,but otherwise I'll let the youngster find a rusted indy to sort it out and help him with the cost if necessary. Thanks to all who assisted. I have a much better understanding of the later AC systems now Dan ___ http://www.okiebenz.com For new and used parts go to www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com ___ http://www.okiebenz.com For new and used parts go to www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
Re: [MBZ] 300 ACC Issue
A large pair of channel locks will work to hold the clutch to remove the bolt. You also need a pair of snap ring pliers, if I remember correctly, but this is NOT a difficult job. Peter On Mar 16, 2012, at 8:00 PM, Dan Penoff wrote: That may be true, but in all honesty, I just don't have the time or desire to tear into this thing. If it as something a little less involved, fine, but otherwise I'll let the youngster find a rusted indy to sort it out and help him with the cost if necessary. Thanks to all who assisted. I have a much better understanding of the later AC systems now Dan On Mar 16, 2012, at 8:41 PM, Jim Cathey wrote: I can't see attempting to replace the clutch in car since I don't have all the required tools. So far as I know there's only one special tool, and it's not too expensive if you find the right one. Less than cans of refrigerant! (I made my own, but wish I hadn't had to.) See: http://userweb.windwireless.net/~jimc/mb190dlog.html#clutchtool -- Jim ___ http://www.okiebenz.com For new and used parts go to www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com ___ http://www.okiebenz.com For new and used parts go to www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com ___ http://www.okiebenz.com For new and used parts go to www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
Re: [MBZ] 300 ACC Issue
Hi Manfred, Do you have ester oil in your A/C system or did you flush and change it? I'm thinking of putting Envirosafe in one of mine but wondered if oil had to be changed since I just flushed the system and put in fresh ester oil, a new compressor. and a new filter unit. I have a good vacuum pump. Thanks, Gerry P.S. I have a couple of the ram chips out of a no-name laptop that you can have if the 512s don't work. Contact me offline if you need them. ... From: MG trainpain2...@yahoo.com To: Mercedes Discussion List mercedes@okiebenz.com Sent: Friday, March 16, 2012 7:33 PM Subject: Re: [MBZ] 300 ACC Issue Just this morning I put two cans of envirosafe into my 123 AC system. It was all but empty so it was just the right amount. I am now getting 32 deg at the center vents going down the road. I had 134a in there before and was happy to get 40. I forget what I paid for the envirosafe but it wasn't anywhere near $27 a can. Look for it on the net. I'm sold on it. Manfred Date: Fri, 16 Mar 2012 10:42:47 -0400 From: Dan Penoff lwb...@yahoo.com Subject: Re: [MBZ] 300 ACC Issue Tests this morning would indicate that the compressor clutch is open circuited. Ohmmeter readings are open and applying B+ directly to the connector at the compressor yield no response. Sigh. I can't see attempting to replace the clutch in car since I don't have all the required tools. What kind of a job is replacing the compressor on this beast like? It's really stuck in there, but I'm just looking at it from the top. Also, this is currently an R12 system. I really don't want to convert it, as R134a in these systems just doesn't cut it in this climate. I have one can of R12, which I am sure will not be enough to charge the system. Can I go with propane and not have to hassle with purging the system and all that? Suggestions are welcome. I have not yet convinced myself that I want to do this, but I don't have any trusted auto AC people around here to work with, either... Thanks, Dan ___ http://www.okiebenz.com For new and used parts go to www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com - No virus found in this message. Checked by AVG - www.avg.com Version: 10.0.1424 / Virus Database: 2113/4875 - Release Date: 03/16/12 ___ http://www.okiebenz.com For new and used parts go to www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
Re: [MBZ] 300 ACC Issue
I can't add much to this other than when I've seen MAS before its Mass Air Sensor which measures airflow for the fuel injection system. If thats true on this car too it makes sense that the engine dies when its unplugged... -Curt Date: Wed, 14 Mar 2012 16:37:02 -0400 From: Dan Penoff lwb...@yahoo.com To: Mercedes List mercedes@okiebenz.com Subject: [MBZ] 300 ACC Issue Message-ID: a9c5ec1a-0804-46f1-9f97-a1e2e0f81...@yahoo.com Content-Type: text/plain; charset=us-ascii OK, guys, pile on. I'm in unfamiliar territory here, and could really use some direction: 1992 300E 2.6, complaint is AC compressor won't come on. Original complaint was that the #7 fuse was blowing, killing all ACC related functions. Fuse was replaced, and now ACC functions as expected, that is, fan speeds, doors, heat/defrost, etc. Everything works but the AC compressor. I shorted out the low pressure switch with no result. Checked for power in the harness to the low pressure switch in reference to ground and got nothing. This model has a MAS relay which may or may not play a part in this, but I don't have a schematic, so if anyone does, I would really appreciate you forwarding a copy to me, as that would make my life significantly easier in identifying the problem. If I pull the MAS relay while the car is running the engine dies, as I would expect. Since it's supposed to interface with all sorts of things like the fuel pump and other goodies, it appears to be working as intended, as everything else on the car works perfectly. I have to believe there is a failure in getting a signal to the compressor clutch, but without a diagram I'm swinging in the proverbial wind. I would put B+ to the clutch, but I'm unsure of what wire is which, and I don't want to smoke the speed sensor in the process. From what I can glean, it appears that power comes in, goes through the low pressure switch, and then on to the compressor clutch. That's an educated guess based on what I am seeing, but I'm not tearing harnesses apart, either. There are three wires going to a connector on the top of the compressor, two of which go off in a separate harness that heads up under the air cleaner. The remaining wire goes to one side of the low pressure switch. I am assuming the two that head into the engine harness are for the speed sensor. Dan ___ http://www.okiebenz.com For new and used parts go to www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
[MBZ] 300 ACC Issue
OK, guys, pile on. I'm in unfamiliar territory here, and could really use some direction: 1992 300E 2.6, complaint is AC compressor won't come on. Original complaint was that the #7 fuse was blowing, killing all ACC related functions. Fuse was replaced, and now ACC functions as expected, that is, fan speeds, doors, heat/defrost, etc. Everything works but the AC compressor. I shorted out the low pressure switch with no result. Checked for power in the harness to the low pressure switch in reference to ground and got nothing. This model has a MAS relay which may or may not play a part in this, but I don't have a schematic, so if anyone does, I would really appreciate you forwarding a copy to me, as that would make my life significantly easier in identifying the problem. If I pull the MAS relay while the car is running the engine dies, as I would expect. Since it's supposed to interface with all sorts of things like the fuel pump and other goodies, it appears to be working as intended, as everything else on the car works perfectly. I have to believe there is a failure in getting a signal to the compressor clutch, but without a diagram I'm swinging in the proverbial wind. I would put B+ to the clutch, but I'm unsure of what wire is which, and I don't want to smoke the speed sensor in the process. From what I can glean, it appears that power comes in, goes through the low pressure switch, and then on to the compressor clutch. That's an educated guess based on what I am seeing, but I'm not tearing harnesses apart, either. There are three wires going to a connector on the top of the compressor, two of which go off in a separate harness that heads up under the air cleaner. The remaining wire goes to one side of the low pressure switch. I am assuming the two that head into the engine harness are for the speed sensor. Dan ___ http://www.okiebenz.com For new and used parts go to www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
Re: [MBZ] 300 ACC Issue
You're very close, if my 124 diesel knowledge applies. The KLIMA relay compares engine speed to compressor speed to decide if the serpentine belt is slipping. Sounds like that signal has been interrupted. Could be bad speed coil on the compressor, bad KLIMA, or bad engine speed pick-up. Could also be bad clutch on the compressor, or bad PBU. Hard to track down with out knowing which wires connect to what. -- Max Dillon Charleston SC '95 E300, '87 300TD ___ ___ http://www.okiebenz.com For new and used parts go to www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
Re: [MBZ] 300 ACC Issue
All quite possible, however, I have yet to determine that the MAS relay has taken the place of the KLIMA relay (which does not exist on this particular chassis.) That's why I really need a schematic. With that I could at least pin things down... Thanks! Dan On Mar 14, 2012, at 5:16 PM, Max wrote: You're very close, if my 124 diesel knowledge applies. The KLIMA relay compares engine speed to compressor speed to decide if the serpentine belt is slipping. Sounds like that signal has been interrupted. Could be bad speed coil on the compressor, bad KLIMA, or bad engine speed pick-up. Could also be bad clutch on the compressor, or bad PBU. Hard to track down with out knowing which wires connect to what. -- Max Dillon Charleston SC '95 E300, '87 300TD ___ ___ http://www.okiebenz.com For new and used parts go to www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com ___ http://www.okiebenz.com For new and used parts go to www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
Re: [MBZ] 300 ACC Issue
Read #2 and #3 here http://www.w124performance.com/service/W126/Index/Misc.htm I think you are right, that the wire from the low pressure switch to the comp is the clutch power wire. With it off at the comp, measure resistance of the terminal on the compressor to ground. Open or near 0 resistance means the coil is bad. (obviously) I don't know what the resistance should be, probably 1.5 to 3 ohms. is a good coil. You could also have someone turn on the AC while you are measuring the voltage of that wire to ground. It should show 12v for a short time, until the system detects the pulley is not turning. It is possible the everything relay replaced the Klima. Or maybe they moved the Klima on that model. OK, guys, pile on. I'm in unfamiliar territory here, and could really use some direction: 1992 300E 2.6, complaint is AC compressor won't come on. Original complaint was that the #7 fuse was blowing, killing all ACC related functions. Fuse was replaced, and now ACC functions as expected, that is, fan speeds, doors, heat/defrost, etc. Everything works but the AC compressor. I shorted out the low pressure switch with no result. Checked for power in the harness to the low pressure switch in reference to ground and got nothing. This model has a MAS relay which may or may not play a part in this, but I don't have a schematic, so if anyone does, I would really appreciate you forwarding a copy to me, as that would make my life significantly easier in identifying the problem. If I pull the MAS relay while the car is running the engine dies, as I would expect. Since it's supposed to interface with all sorts of things like the fuel pump and other goodies, it appears to be working as intended, as everything else on the car works perfectly. I have to believe there is a failure in getting a signal to the compressor clutch, but without a diagram I'm swinging in the proverbial wind. I would put B+ to the clutch, but I'm unsure of what wire is which, and I don't want to smoke the speed sensor in the process. From what I can glean, it appears that power comes in, goes through the low pressure switch, and then on to the compressor clutch. That's an educated guess based on what I am seeing, but I'm not tearing harnesses apart, either. There are three wires going to a connector on the top of the compressor, two of which go off in a separate harness that heads up under the air cleaner. The remaining wire goes to one side of the low pressure switch. I am assuming the two that head into the engine harness are for the speed sensor. Dan ___ http://www.okiebenz.com For new and used parts go to www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com ___ http://www.okiebenz.com For new and used parts go to www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
Re: [MBZ] 300 ACC Issue
I did attempt to check for voltage from the ACC system to the low pressure switch and ultimately the compressor clutch, but I turned things on and then got over to the connections, so it would have been a good 30 seconds before I ever got the Fluke's leads on the connectors. It's such a small gauge wire, I'm surprised it would provide power to the clutch, as it draws a good 3-4 amps, I believe. I did not attempt to check the resistance of the clutch coil, however, since I'm not getting power to it in the first place, I don't think it's necessarily the problem. I do have the values for it, however (thanks, Wilton!) Thanks for the suggestions. I know the 126 chassis ACC well, so I'm not that far out of my comfort zone, but this system is definitely different, so hopefully someone out there has a diagram... Dan On Mar 14, 2012, at 6:05 PM, Dieselhead wrote: Read #2 and #3 here http://www.w124performance.com/service/W126/Index/Misc.htm I think you are right, that the wire from the low pressure switch to the comp is the clutch power wire. With it off at the comp, measure resistance of the terminal on the compressor to ground. Open or near 0 resistance means the coil is bad. (obviously) I don't know what the resistance should be, probably 1.5 to 3 ohms. is a good coil. You could also have someone turn on the AC while you are measuring the voltage of that wire to ground. It should show 12v for a short time, until the system detects the pulley is not turning. It is possible the everything relay replaced the Klima. Or maybe they moved the Klima on that model. ___ http://www.okiebenz.com For new and used parts go to www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
Re: [MBZ] 300 ACC Issue
I have found a reference to the MAS and what it does in the AC manual, but they use that darned breakout box to do the troubleshooting. If I could find a schematic I could figure this out in short order, but the ones I have been looking at are for older models that use the KLIMA relay and not the MAS. Dan On Mar 14, 2012, at 6:05 PM, Dieselhead wrote: Read #2 and #3 here http://www.w124performance.com/service/W126/Index/Misc.htm I think you are right, that the wire from the low pressure switch to the comp is the clutch power wire. With it off at the comp, measure resistance of the terminal on the compressor to ground. Open or near 0 resistance means the coil is bad. (obviously) I don't know what the resistance should be, probably 1.5 to 3 ohms. is a good coil. You could also have someone turn on the AC while you are measuring the voltage of that wire to ground. It should show 12v for a short time, until the system detects the pulley is not turning. It is possible the everything relay replaced the Klima. Or maybe they moved the Klima on that model. OK, guys, pile on. I'm in unfamiliar territory here, and could really use some direction: 1992 300E 2.6, complaint is AC compressor won't come on. Original complaint was that the #7 fuse was blowing, killing all ACC related functions. Fuse was replaced, and now ACC functions as expected, that is, fan speeds, doors, heat/defrost, etc. Everything works but the AC compressor. I shorted out the low pressure switch with no result. Checked for power in the harness to the low pressure switch in reference to ground and got nothing. This model has a MAS relay which may or may not play a part in this, but I don't have a schematic, so if anyone does, I would really appreciate you forwarding a copy to me, as that would make my life significantly easier in identifying the problem. If I pull the MAS relay while the car is running the engine dies, as I would expect. Since it's supposed to interface with all sorts of things like the fuel pump and other goodies, it appears to be working as intended, as everything else on the car works perfectly. I have to believe there is a failure in getting a signal to the compressor clutch, but without a diagram I'm swinging in the proverbial wind. I would put B+ to the clutch, but I'm unsure of what wire is which, and I don't want to smoke the speed sensor in the process. From what I can glean, it appears that power comes in, goes through the low pressure switch, and then on to the compressor clutch. That's an educated guess based on what I am seeing, but I'm not tearing harnesses apart, either. There are three wires going to a connector on the top of the compressor, two of which go off in a separate harness that heads up under the air cleaner. The remaining wire goes to one side of the low pressure switch. I am assuming the two that head into the engine harness are for the speed sensor. Dan ___ http://www.okiebenz.com For new and used parts go to www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com ___ http://www.okiebenz.com For new and used parts go to www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com ___ http://www.okiebenz.com For new and used parts go to www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
Re: [MBZ] 300 ACC Issue
Dan, 'Just set you a comp. clutch schematic. Is it the one you need? Wilton - Original Message - From: Dan Penoff lwb...@yahoo.com To: Mercedes Discussion List mercedes@okiebenz.com Sent: Wednesday, March 14, 2012 7:00 PM Subject: Re: [MBZ] 300 ACC Issue I have found a reference to the MAS and what it does in the AC manual, but they use that darned breakout box to do the troubleshooting. If I could find a schematic I could figure this out in short order, but the ones I have been looking at are for older models that use the KLIMA relay and not the MAS. Dan On Mar 14, 2012, at 6:05 PM, Dieselhead wrote: Read #2 and #3 here http://www.w124performance.com/service/W126/Index/Misc.htm I think you are right, that the wire from the low pressure switch to the comp is the clutch power wire. With it off at the comp, measure resistance of the terminal on the compressor to ground. Open or near 0 resistance means the coil is bad. (obviously) I don't know what the resistance should be, probably 1.5 to 3 ohms. is a good coil. You could also have someone turn on the AC while you are measuring the voltage of that wire to ground. It should show 12v for a short time, until the system detects the pulley is not turning. It is possible the everything relay replaced the Klima. Or maybe they moved the Klima on that model. OK, guys, pile on. I'm in unfamiliar territory here, and could really use some direction: 1992 300E 2.6, complaint is AC compressor won't come on. Original complaint was that the #7 fuse was blowing, killing all ACC related functions. Fuse was replaced, and now ACC functions as expected, that is, fan speeds, doors, heat/defrost, etc. Everything works but the AC compressor. I shorted out the low pressure switch with no result. Checked for power in the harness to the low pressure switch in reference to ground and got nothing. This model has a MAS relay which may or may not play a part in this, but I don't have a schematic, so if anyone does, I would really appreciate you forwarding a copy to me, as that would make my life significantly easier in identifying the problem. If I pull the MAS relay while the car is running the engine dies, as I would expect. Since it's supposed to interface with all sorts of things like the fuel pump and other goodies, it appears to be working as intended, as everything else on the car works perfectly. I have to believe there is a failure in getting a signal to the compressor clutch, but without a diagram I'm swinging in the proverbial wind. I would put B+ to the clutch, but I'm unsure of what wire is which, and I don't want to smoke the speed sensor in the process. From what I can glean, it appears that power comes in, goes through the low pressure switch, and then on to the compressor clutch. That's an educated guess based on what I am seeing, but I'm not tearing harnesses apart, either. There are three wires going to a connector on the top of the compressor, two of which go off in a separate harness that heads up under the air cleaner. The remaining wire goes to one side of the low pressure switch. I am assuming the two that head into the engine harness are for the speed sensor. Dan ___ http://www.okiebenz.com For new and used parts go to www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com ___ http://www.okiebenz.com For new and used parts go to www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com ___ http://www.okiebenz.com For new and used parts go to www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com ___ http://www.okiebenz.com For new and used parts go to www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
Re: [MBZ] 300 ACC Issue
Wilton, It's certainly closer to anything I have seen so far. What I recall is that the MAS only had four populated sockets (pins) in the relay socket, which is why I'm confused by the depiction of at least seven connections. I won't get to see the car again until tomorrow morning, but I'll verify what I have against the drawing you sent. At least that way I might be able to do some voltage and continuity checks to narrow things down. Thanks! Dan On Mar 14, 2012, at 8:14 PM, WILTON wrote: Dan, 'Just set you a comp. clutch schematic. Is it the one you need? Wilton - Original Message - From: Dan Penoff lwb...@yahoo.com To: Mercedes Discussion List mercedes@okiebenz.com Sent: Wednesday, March 14, 2012 7:00 PM Subject: Re: [MBZ] 300 ACC Issue I have found a reference to the MAS and what it does in the AC manual, but they use that darned breakout box to do the troubleshooting. If I could find a schematic I could figure this out in short order, but the ones I have been looking at are for older models that use the KLIMA relay and not the MAS. Dan On Mar 14, 2012, at 6:05 PM, Dieselhead wrote: Read #2 and #3 here http://www.w124performance.com/service/W126/Index/Misc.htm I think you are right, that the wire from the low pressure switch to the comp is the clutch power wire. With it off at the comp, measure resistance of the terminal on the compressor to ground. Open or near 0 resistance means the coil is bad. (obviously) I don't know what the resistance should be, probably 1.5 to 3 ohms. is a good coil. You could also have someone turn on the AC while you are measuring the voltage of that wire to ground. It should show 12v for a short time, until the system detects the pulley is not turning. It is possible the everything relay replaced the Klima. Or maybe they moved the Klima on that model. OK, guys, pile on. I'm in unfamiliar territory here, and could really use some direction: 1992 300E 2.6, complaint is AC compressor won't come on. Original complaint was that the #7 fuse was blowing, killing all ACC related functions. Fuse was replaced, and now ACC functions as expected, that is, fan speeds, doors, heat/defrost, etc. Everything works but the AC compressor. I shorted out the low pressure switch with no result. Checked for power in the harness to the low pressure switch in reference to ground and got nothing. This model has a MAS relay which may or may not play a part in this, but I don't have a schematic, so if anyone does, I would really appreciate you forwarding a copy to me, as that would make my life significantly easier in identifying the problem. If I pull the MAS relay while the car is running the engine dies, as I would expect. Since it's supposed to interface with all sorts of things like the fuel pump and other goodies, it appears to be working as intended, as everything else on the car works perfectly. I have to believe there is a failure in getting a signal to the compressor clutch, but without a diagram I'm swinging in the proverbial wind. I would put B+ to the clutch, but I'm unsure of what wire is which, and I don't want to smoke the speed sensor in the process. From what I can glean, it appears that power comes in, goes through the low pressure switch, and then on to the compressor clutch. That's an educated guess based on what I am seeing, but I'm not tearing harnesses apart, either. There are three wires going to a connector on the top of the compressor, two of which go off in a separate harness that heads up under the air cleaner. The remaining wire goes to one side of the low pressure switch. I am assuming the two that head into the engine harness are for the speed sensor. Dan ___ http://www.okiebenz.com For new and used parts go to www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com ___ http://www.okiebenz.com For new and used parts go to www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com ___ http://www.okiebenz.com For new and used parts go to www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com ___ http://www.okiebenz.com For new and used parts go to www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
Re: [MBZ] 300 ACC Issue
That is too long. Hook it up so that you can see the readout, then turn on the switch. the old mechanical VOMS were good for this because you'd see the needle start up, then go back to 0. It will only be a blip. ___ http://www.okiebenz.com For new and used parts go to www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
Re: [MBZ] 300 ACC Issue
Compressor clutch coils can go bad, they're in a harsh environment. Connectors thereto, also. But it sounds KLIMA-ish to me. The WOT switch can affect the AC too. -- Jim ___ http://www.okiebenz.com For new and used parts go to www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
Re: [MBZ] 300 ACC Issue
So, no Klima on Dan's model. The linked post below makes it appear that the MAS may control A/C functions. http://forums.mercedesclub.org.uk/showpost.php?p=126705postcount=13 Post #4 here, says something different: http://mbworld.org/forums/190e-w201/48220-c-compressor-relay-92-190e-2-6-a.html Hmmm... if one of these relays is taking over some Klima functions, I wonder (shooting from the hip) if it works like the Klima does on my '85 W123… if freon pressure is lost, a pressure switch tells the Klima to turn off the compressor solenoid, saving the compressor from damage. I know they changed the configuration and function of this thing many, many times but here's my schematic (all I can find)… maybe it'll jog a memory or point to a possibility until the real schematic appears. https://picasaweb.google.com/lh/photo/GMQYuBJUv3hTB_4vilWnuB_L548h0FhsE9Lwz-quTRM?feat=directlink Dave SoCal For completion, according to the manual the two other functions on a 1985 W123 Klima are: (1) when the engine is started, the relay keeps the compressor solenoid off until 10 seconds after the engine speed has reached 600 RPM. This improves engine speed stabilization after startup. (2) with engine speed less than 1050 RPM, when the accelerator is floored, the compressor solenoid is released until the engine reaches 2150 RPM or the accelerator is released. This function is controlled by a microswitch on the valve cover. On Mar 14, 2012, at 6:22 PM, Jim Cathey wrote: Compressor clutch coils can go bad, they're in a harsh environment. Connectors thereto, also. But it sounds KLIMA-ish to me. The WOT switch can affect the AC too. -- Jim ___ http://www.okiebenz.com For new and used parts go to www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
