Which Fuse Are License Plate Lamps On?

tgreif · February 7, 2008

2004 Silverado SS. For some reason, both license plate lamps have gone out out. I'm in the Chicago area and right now with the snow and slop, I'm not looking to crawl around underneath to troubleshoot this. The manual gives no clue which fuse this circuit is on.

minibike132 · February 9, 2008

The left license lamp is on the LR PARK fuse and the right license lamp on the RR PARK fuse both in the under hood fuse block. Probably not the fuse. Do your rear parking lamps work. Both bulbs probably burned out and you didn't notice one was out till they both went.

tgreif · February 9, 2008

Thanks for the advice. Parking lamps (tail lamps) work just fine. I checked both underhood fuses - also fine. Pulled one of the bulbs and bench tested it with a 12V power supply. Bulb is fine. Next move is to disconnect the chassis connector on rear frame member and test for power at the connector pins. I'll post back what I find.

SKYrado03 · February 9, 2008

Does the receptical itself have a good ground, or doesn't it need one?

tgreif · February 10, 2008

Well, well, well - looky here. What I assumed to be my bone stock, pristine little silverado SS has been in fact, "customized" electrically, shall we say. I removed the rear chassis harness, disassembled it, and found a couple wires clipped and capped off with electrical tape. I remember when I bought this truck, the left rear taillight was very dim - not completely out, just very dim. Fuse replacement cured it. It seems that someone else before me decided they knew how to "fix" the problem by cross wiring some circuits and just eliminating some circuit return paths. I'll figure this circuit out and fix it right.

For what it's worth, I'm an old fart engineer that used to restore old mid-60s corvettes. Electrical stuff is what I really love. While I feel somewhat useless today with all the new computerized stuff on vehicles, I'd love to take some of these digital dorks designing this stuff back to the sixties and let them try and figure out how to solve the problems associated with phantom grounds on the old fiberglass vettes. Poetic justice, eh?

Does anyone happen to have an on-line source for a wiring diagram of the tail/stop circuit and harness?