Hi, working on a C1500 with 4.3. Had a dead battery this morning so I cleaned up the bat terminals and jumpstarted it and the Message Center battery light was lit and the guages/lights were jumping/flickering all over the place. Had Autozone test the alternator and it was fine on their bench tester so I put a new battery in it, reinstalled the alternator and had autozone test with the handheld unit in the vehicle while running. They said the alt was putting out a little low. Looked to be in the low 12s. Bat light on the dash stays on most of the, only going out very briefly every once in a while, and voltage gauge and dash lights were still jumping around. So I swapped out the alternator. No joy, same symptoms. If I kick the rpms up to 1k the volt gauge shows around 14 which is what I would expect so I think it's charging okay and functional but the visible symptoms are troublesome. I'm suspecting a bad ground somewhere. Thought some of the more experienced folks on the board might have some good pointers or connections to inspect etc. I hate, hate, hate, electrical gremlins!