The idiot light on my 65 Cutlass for the temperature does not light up when the key is turned on and the engine is not running. I have grounded the wire at the sending unit and the light lights. This tells me that the bulb and wiring are OK. I changed the sending unit and I still have the problem.

I would like this feature to work, can anyone give me a trouble shooting procedure for this?

 

One terminal on the plug on the back of the instrument cluster should have two green wires.

One should go to the temp. sender, the other should go to the ignition switch.

The terminal on the ignition switch with the green wire should be grounded when the ignition switch is turned to the START position.

The problem is somewhere between the cluster plug and the ground for the ignition switch, including connections, wires, and switch.

Yet another example of how throwing parts at a problem is not the fastest or cheapest way to fix it.

- Eric

 

Thanks, I will check it out.