Now that I have an ammeter in the circuit, I think the antenna control circuitry is what is causing my battery to be drained every other week or so in the '92 300D. I can park the car, turn the key back one position so the engine stops, but the radio is still on. There is around 1-2 amps of drain (glove box light is also on - the ammater is in the glove box). The drain goes up to 3-4 amps when I turn the radio off and tha antenna retracts, then stays there for 10-20 seconds after the motor stops running. I hear a click from the rear of the car, and the ammeter goes to zero. The length of time from the end of the motor run to the click is not consistent. I can't hear the click if the engine is running, which is my usual mode of operation - turn off radio, then kill engine.
It's also interesting to watch the the current immediately after starting the engine - when it's cold (below 40F), there is a drain of ~30 amps, the tapers off to ~10 amps over 15-30 seconds, then a click, and the meter jumps up to a 30 amp charge, which slowly drops to zero over a couple of miles. When the engine is warm, the meter jumps to charging almost immediately after starting. Seems there's some clever tempreature dependent timing going on in the glow plug relay. On Sat, Feb 19, 2011 at 9:23 AM, Peter Frederick <psf...@earthlink.net>wrote: > There is a fault in the antenna motor controller if the battery goes dead > -- it must time out when the mast stops (as it does when it's all the way up > or down, in fact) -- there is no difference between the mast being stuck an > inch or two up and fully down as far as the guts go. > > Unplug it with the mast all the way up until you can get a replacement. > They used to be fairly common in junkyards, don't know about that now. > Same motor for all of them, just the mast post was different. > > Peter > -- > OK Don 2001 ML320 1992 300D 2.5T 1990 300D 2.5T 1997 Plymouth Grand Voyager _______________________________________ 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
