I have an 85' Trans Am, and I am just getting around to getting the gauge cluster to function. When I got the car, it had no engine or transmission and all of the wires under the dash and in the engine bay were unplugged or cut. I have figured all of them out except for the ones that plug into the back of the fuse box. One unknown connector has 4 wires, 2 of which are gray and pink with a black stripe. There appear to be way too many hookup locations on the fuse box for the number of connectors I have available, and the 4 wire connector does not fit into any of them.

 

To be clear, here is the connector in question. Side note: all of my gauges are working except the tach. It goes to zero calmly like it should when the engine is turned off but when I start it up, the needle immediately goes to max. I have the white wire that supplies the signal going to the tach post of the distributor. Is it a bad tach, or a bad distributor? When the wire is unplugged from the distributor, the tach needle bounces a bit on startup then sets back to zero.

 

That looks a lot like it is a cruise control plug for the turn signal stalk... which your cruise control is probably long gone, judging by your original post....

Tach, may be shot. If your tach signal from the dist is bad... odds are the car isn't running as the tach is hooked to the ground of the coil.

 

Yeah I don't think I'm at the stage where I'm worrying about the cruise control too much. And as for the tach, I'm going to get another tach and hook it up to see what the problem is. Thank you!

Also, I took a picture of a green plastic box under the steering wheel to the right. It keeps making a buzzing noise. Any idea what it is? A light on my cluster keeps lighting up (looks like a slash with a dot in the middle of it) I don't know if that's related. Every time I try to take a picture of it, it turns off.

 

The blue box is the door dinger, chime box, audible warning - doohickey. When your headlights are on and you open the door, it buzzes or dings. When your key's in the ignition and you open the door... Try unplugging the box and see if the noise goes away to isolate the issue.

The green box is the horn relay. If you think it's buzzing, unplug it and see if the buzzing stops. If the horn relay is buzzing, and you're not pushing the horn button, there's probably a short somewhere in the column or the horn button itself.