My 2002 gmc 1500 PU lost all gauges and most lights. Driving on a dirt road all the dash lights and gauges started flashing on and off. They all finally quit. All that works is turn signals and illumination lights with head lights. I used my buddies instrument panel from a 2001 gmc. Plug it in and still same problem with his. I tested all fuses with a test light 3 times in both fuse panels. Even pulled out fuses and reinstalled to make sure good contact. Checked for a loose connecters under dash and under fuse panel under the hood. Wiggled wire harnesses and dash still dose not come on. I’ve disconnected the battery and reconnected to reset with still no luck. Do you have any ideas to try next. Thanks Mike
Might be a broken connection inside/backside of the fuse panel, or in the middle of a harness.
You (or a good mechanic) needs to read the wiring diagram and do some tracing.
The problem might be with the Body Relay Block.
Ignition fuse #1, 10 amp, hot in start/run, supplies power to the Body Relay Block, which then supplies power to the instrument cluster.
Tester
In other instrument clusters they need to be reprogrammed for mileage etc. Not sure if this applies to you but at this point you might be better off looking at cracked solder joints and corrosion at the main connection and reusing the the original. If items go out one by one it is usually a stepper motor that can be replaced if you don’t mind some tedious soldering to save a few hundred bucks. Since the connection should be good at cluster, assumed, look at the other end of the cable! EDIT!!! Posted before testers comment, I type slow, try tester’s solution first!