Hi Gang,

I'm new to the forum and I sure could use the help of one of you electrical experts today.

The short version to my issue is this:

I have a 1991 Silverado K1500 4x4 with the 5.7 block, and I installed new headlights and turn signal lights last year.

She runs great and up until now I have had no electrical issues with the truck, and the alternator is fairly new with no issues.

I hit a really nasty pot hole about two weeks ago and my headlights, interior dash lights, horn, radio, and cigarette lighter have all stopped working.

I checked all of the usual suspects like the ground wire that goes to the back of the dash, the ground on the engine, the wires that bolt to the fire wall under the black plastic cover (that's located above & behind the block) the headlight connections, and I even put a new headlight switch in, but none of those items seem to be the problem and it's killing me.

Not only can I not drive at night but I have no way to charge my phone while I'm driving.

My turn signals work, and I believe my brake lights work, and for some strange reason, the green lights within the temperature control box work, but that's about it.


Any help here would be greatly appreciated, thanks......

 

Check all your frame grounds, could be one is cut due to the pot hole, and the frame coming in contact, and either mashing or cutting it.

 

I do agree a ground is probably at fault, but don’t rule anything out until you’ve tested it. I can’t remember exactly where but the headlights ground on the radiator support - you may have to remove the grill to see them.

Another way to test - Disconnect one of the headlights (Doesn’t matter which one, just make sure you know if the circuit is bright or dim so the results don’t fool you) and check for power using a test light direct to battery ground - or use a jumper wire to provide direct battery ground to the headlight. If it lights, it’s a ground problem - if it doesn’t, or it lights very dimly, it’s a power supply issue. Use a meter to verify voltage.

It looks like the courtesy and panel lamps fuses are the power supply for the devices you listed. If power supply is the problem, check that both those fuses are good (use test light to verify power on both sides of the fuse when it’s installed in the fuse box - many times I’ve thought a fuse looked good but it tested bad - also make sure to check them with the key on).

 

Thanks guys, much appreciated, and I'll check all of these things.......