After complete water damage, instrument panel not working?

XSHINE25

MEMBER
1992 GMC SIERRA
6 CYL
2WD
AUTOMATIC
210,000 MILES

1992 GMC Sierra C1500 4.3L, after complete water damage, instrument panel not working, needles dont work(speedometer, temp, fuel level, etc), illumination night lights work, turn signals, high beams, seat belt bulbs work, while service engine and battery light does not. Is there a relay or is instrument panel bad? Already replace battery and alternator.

1 Reply

SQM

MECHANIC
6,383 POSTS

Hello,

It sounds like there is a short in the harness for the gauge cluster.
First check all the fuses both under the dash and the under the hood. There are several fuses that can impact the gauge. You should be able to do this by just using a test light.

After the fuses you will need to check the wiring harness. Since it is been on a water damage it could have corroded connectors and or bad ground connection. Which will make the instruments inoperative.
Trace the wires to find any open or short for the cluster harness. See attached wiring schematics.

Here is some helpful info on how to check wiring:

https://www.2carpros.com/articles/how-to-check-wiring
https://www.2carpros.com/articles/how-to-check-an-electrical-relay-and-wiring-control-circuit
https://www.2carpros.com/articles/how-to-check-a-car-fuse

I have attached diagrams for your reference.

Please let me know of any questions.

Thank you.

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