WIRING INFO

Go to:

http://spad.sytes.net/fiero/manuals/

Download the "Pontiac_Fiero_1986_Service _Manual"

It's 76Meg, so high speed is an asset.

All the electrical information is in the later sections. Most of the information will be the same. What type of problem is it...I may be able to help you narrow it down.

Chay

temp gauge is not working, we have narrowed it down to two wires touching somewhere along the harness we think...as there is resistance to both wires when tested when disconected ....at this point we have found nothing wrong with the harnes up to the bulkhead, .  My mechanic would like to know what the electical scymatics are on the bulkhead, not sure why just siad I would find them for him.  Since I have just spent over 4 grand on a new rebuilt longblock I dont want to take any chances of driving this car any distance without the darn temp gauge working.

thankyou so much for your guys help

Laura

For troubleshooting:

"C500" is the bulkhead connector...the one near the battery. Disconnect it and find terminal "c2". It should be embossed on the connector, or something like "C1" and then you have to count up from there. It will be a light green on the cabin side and a dark green with white tracer on the engine side as indicated above. Connect a wire from the light green side of the connector to ground. This will simulate a high temperature condition (Needle pinned). I think the ignition switch will have to be in "run", NOT bulb test. Remove the wire, this will simulate a low temp condition. This is essentially what the ignition switch is doing in this circuit...it's a test to see if your guage is working. If you are in bulb test or start, the guage should be pinned to the high temp side.

Anyway, with the wire thing:

If the guage doesn't move with the wire installed, the problem is on the cabin side of the C500 connector. If it does move, the problem is on the engine side of the C500 connector.

If it's on the engine side, pull the wire off the sender. Ground it there and repeat the test. IF it doesn't work, the porblem is the wire. If it does work, the problem is the sender.

If it's on the cabin side, I'd take the dash apart to get to the connector for the guages. It's called "C3". Find terminal 11 on it and it should be a light green. Ground this terminal and repeat the test. If it works, then move towards the C500 connector wherever you can gain access to it (If this is it, the problem is likely in the 'clear' connector behind the center console by the ECM). Or, splice in a new wire from the guage connector to the C500 connector.

Hope this helps,

Chay