Temp Guage Problem

[Mach 5]

I was driving my friends 535 last night and I noticed that the temp guage pegs hot as soon as the ignition switch is it turned to the run position, tells me it is grounding somewhere. I could not find the wiring diagram in the Bentley manual for this circuit. The problem started after he had it serviced and the repair shop reset the SI lights. The shop voluntered that the guage started doing this after they reset the lights yet they could find nothing wrong. I was wondering if anyone has had this happen to them and if I can get a wiring diagram for the temp guage.
Ben

[KC Ron Carter]

This is an e24 but the same issues.

http://members.roadfly.com/kcroncarter/etm126.htm


Pin #4 on the diagnostic

And yes the sensor signals must go through the SI.

Later,

[Mach 5]

Thanks Ron for the diagram. I spent some time on it this weekend but to no avail. Has anyone had this problem? I thought that it might be the #4 pin grounding in the diagnostic connector but that was not the case. Where is C101 located on the e28? I guess that I get to keep hunting, I hate electrical problems.
Ben

[TECH]

Doesn't the circuit board have batteries in that car? Take it apart, and you may see battery acid leaking here and there......