After completing replacing the "gauge cluster," my problem is still here. No only does the back-light go out after turning the headlights on, my thermostat gauge moves from complete bottom to complete top after being idle for 1 minutes.

The previous gauge cluster had a temperature gauge that was extremely volatile, and would steady after a few thumps with my palm. Now the new one doesn't even respond after topping off.

The AC does kick on both "radiator" fans, but the fans do not come on after the engine is idle and the fan control is turned to the "off" position.

Checked all fuses, and they're all good. Not sure how to check the larger box fuses under the hood, since there is no transparency.

Thanks,

--tj

 

Check temperature sensor resistance. It may be faulty.

Check dimmer control for possible fault leading to loss of back lighting.

W/O AC on, the cooling fans only come on when coolant temp reaches about 194F. In cool weather, this may never happen. Fan control sounds normal to me.

good luck

 

It's possible that some of the lighting problem occurred after installation of a stereo that I installed.

--tj

 

Were you having problems with the gauge cluster before you installed the stereo?

 

Yes, but not with the lighting. The problem with the lighting started after the installation of the radio. E.g., the temperature gauge was having problems before the radio install, but the odometer lighting was working before the stereo installation.

--tj

 

That would have been helpful information in your first post. The temperature gauge and the lighting are two different problems.

For the gauge, unplug the connector from the temperature sending unit. That sensor is on the cylinder head under the distributor and the closest sensor to the front of the engine. That sensor has only one wire going to it.

When you unplug that sensor and the wire does not touch metal, the temperature gauge should stay at cold when you turn the key to the II position. If you ground that wire, the gauge should rise immediately to hot. Do not let the needle reach the top, turn off the key before that happens.

As for the lighting problem, you are going to have to figure out what wire(s) you did not connect properly when you installed the stereo. I am assuming this is an aftermarket stereo where you wired your own conversion harness?

 

The sensor has one green/white wire going to another plug that is hooked to a ground? I've unplugged it, but the gauge starts C and then after 1-minute of idle, it reaches H.

 

The sensor should only have one wire going to it (yellow/green wire?). It should be the sensor closest to where the upper radiator hose attaches to the cylinder head.

 

Yup, it's one wire, but yellow/green.

 

So what were you talking about going to another plug to ground?