It's toast, I think. On the 300D, one wire is the fan switch, should be open, but the other two (two wire plug, if the plug is still intact) is a thermistor. May be a switch and a thermistor on the W126, I'm not sure. Could be a coolant temp switch, too for that matter, you will have to check, I don't have the W126 manuals. I'd replace it -- make sure you know the engine and chassis number, as they changed during production and aren't interchangeable.
Peter On Jun 18, 2008, at 11:09 PM, Luther wrote: > That sensor plug is keyed and cannot be reversed? I've applied > some Deoxit to all of the coolant sensor connectors. I've checked > the resistances of all of the coolant sensors, and the 3 pronged > green (see the picture link) showed open to ground, and open across > all 3 combinations of prongs. Sounds like it isn't good? > > picture is here: http://www.gulseth.net/photos/coolant-sensor.jpg > Luther > > On Wed, 18 Jun 2008 15:36:34 -0500, OK Don <[EMAIL PROTECTED]> wrote: > >> I believe that the coolant sensor for the ACC is in a dual element >> sensor on the engine - one set of pins for the ACC, the other for the >> idle control. The AC on my SDL would turn off the compressor as soon >> as the coolant hit 80C - the PO had reversed the sets of wires on >> that >> sensor. The AC worked great after I switched those two plugs. >> >> On Wed, Jun 18, 2008 at 1:24 PM, Luther <[EMAIL PROTECTED]> wrote: >>> OK, test results are all normal except for the following: >>> Sensor Ground test, Pin 8 (coolant temp)=open >>> Vacuum flaps, pin 8 (short DEF Flap)=1k ohms >>> >>> Maybe I have a bad (hopefully unplugged) coolant sensor. >> > > > > -- > Luther KB5QHU Alma, Ark > '87 300SDL (272,xxx mi) head case > '85 Ford F250 6.9 diesel (x58,xxx mi) > '82 300CD (166 kmi) > '82 300D (74 kmi) getting donor engine-sold > '85 300D (280,176) parts car sans engine > > _______________________________________ > http://www.okiebenz.com > For new parts see official list sponsor: http://www.buymbparts.com/ > For used parts email [EMAIL PROTECTED] > > To Unsubscribe or change delivery options go to: > http://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com _______________________________________ http://www.okiebenz.com For new parts see official list sponsor: http://www.buymbparts.com/ For used parts email [EMAIL PROTECTED] To Unsubscribe or change delivery options go to: http://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
