So I was given a 2004 suburban by a friend. loaded lt, 4x4. 226k miles, more than I like, but it's free. Sunroof was left cracked over winter, got water inside and some mold. I stripped the interior and got it nice and clean. Tonight I was test running the engine, testing everything, figuring out what works and not, seeing if it's worth keeping and putting some money into. I am a mechanic by trade, so.k can most everything myself. After about 10 minutes of running, the radio shut off. Not like dead, just off,.still.showing the clock. 3 seconds later, the door locks all cycled about 3 times, and the dome lights came on, even though the cancel switch was pushed. If I hit the radio power button, it will turn on for a second and back off. Nothing else shuts off. DIC shows all doors still closed. All door switches work constantly. Cycle the key off and back on, radio works, some lights turn off. Anywhere from 2 seconds to 2 minutes it would do the exact same thing. Radio off, locks cycle, dome on. Engine running or not. After about 8 times, it was fine for 10 minutes. Had to stop for the night so came in.
Any ideas? I'm guessing a corrosion based gremlin, but not sure. Unfortunately, my basic scan tool I have at home won't read anything other than engine.