Thread: Confusing Electrical Issue

Alright guys,

I've got a '97 GT and its developed an electrical issue. The original problem is that I'll turn the key over to start the car and all power cuts off to the car like the battery isn't even connected to the car. No hazards, no nothing and the key gets locked into the cylinder and won't let me take it out of the accessory position. We've managed to figure out the short is coming from the main fuse box in the engine bay. You can reach down and pull the fuse box up or wiggle it around and the power comes back to the car. So we went and got a different fuse box from another 3.8l GT, same part number and everything and switched it over and it seems to have fixed the problem but as soon as I start the car the temperature gauge just starts climbing rapidly. The car isn't actually running hot, the gauge is just freaking out and I'm not sure why. I can put the original fuse box back in the car and the gauge goes back to normal and the car starts normally for a couple of days before the original problem pops back up.

So any advice on what I can do?

So how could we make the signal for the gauge connect with the new fuse box?

Your going to have to get a wiring diagram for you exact year and model and find and check the terminal from the fuse box.

Maybe I'm misunderstanding, but everything is exactly the same between the two fuse boxes. All the fuses and connections are good. I'll try and find a diagram in the morning. The one is the Haynes manual shows the wiring for 1997 and up.

Could the problem be something else that I'm missing? We are pretty sure its a short from the one wire hooked up to the black plug on the back side of the fuse box. It seems to connect straight to the big orange fuse right by the main power to the rest of the box. and when we traced the wire from the black plug it goes to the computer.

Was the new fuse box from another 97? As J57 says, if 97 was a 1-yr only, the connector configuration could have changed very slightly to where the temp gauge is connected to some other source with the new fuse box in. So engine temp isn't going up, but it's measuring something else that is.

I know from experience that GM does this. 00-07 Suburbans are all the same, but they changed the pin config in the trailer brake connector in 03. So you needed harness A for 00-02 and harness B for 03-07. The connector was exactly the same, but two pins swapped positions in 03, nobody knows why. Use the wrong harness and it plugs in fine, but trailer brakes don't work.

Ah okay. Makes sense now because the new fuse box was from a 2000. Thank you guys for the advice

Originally Posted by J57ltr

IT'S NOT A SHORT. A short would mean that you would have power and ground connected together. You have an INTERMITTENT connection. That said there are some differences between 97' and 98' up harnesses. You will need to get a wiring diagram for both your 97' and whatever other year car you pulled the fusebox you pulled, and compare them. Chances are that there are a couple of wires that are different. It sounds as though you don't have a signal or power to the temp gauge.

I just went through this with another member on this forum and had a small fire and the only replacement harness is a 97' for a 97'. Tried talking him into switching to 98' and later but there were too many things to change in order to get it working.

I had a hell of a time with my Dad wanting to change his 00' truck with an 06' motor. I had to convince him to change engine parts from his 00' motor to work with the 06' engine and trans, as the differences were significant. Your kinda in the same boat where the 97' is different enough to have to check everything.

Don't use a haynes manual or chilton both are worthless as tits on a boar hog when it comes to a wiring diagram. I am sure someone on here has All Data that can send you a diagram.

Jeff

What he said ^