Short Circuit, Orange Wire

[Jgreemo]

Hi all,

I've got a short to ground in the 20A circuit feeding the dome lights, horn, radio and lighter. Started out as an occasional blown fuse then to a blown fuse a week (often come out in the morning and no lights on with door open) and now blowing immediately.

I've disconnected all the loads based (lights, radio, amp, steering column, horn relay et.) on my wiring diagram from the official service manual and tried running a breaker and short finder but nothing. Breaker will close and the short finder shows no amps flowing through the orange wire, or any where else for that matter so it seems to be the block.

I'm assuming now that it's in the fuse block and while I did take it out and clean it (greasy on the engine bay side but clean on the interior), I didn't actually pull out the orange wire that runs off that fuse. Question is, what can go wrong in a fuse block? I'm going to go through the wiring harness again this weekend and hopefully find something but it's been weeks of poking around under there and nothing so far. I'll also pull the block out as well and have another look but the first pass didn't show anything obvious, like burn marks, worn wires or cracks.

Any help would be appreciated since I would like a radio to keep my 3 y/o happy and some interior lights at night. Also don't want to set the truck on fire.

Thanks,
Jon

[DmaxMaverick]

Check the cigar lighter for a coin or corrosion.

[JohnC]

Ah! Is there an accessory plugged into the lighter? Apparently, there is an incompatibility between some of the plugs and sockets.

[Robyn]

The dome lights are fed power.....and the door switches provide the ground.

Wires that snake through the overhead to feed the lights can rub and short.

Same goes for the wires that feed the under dash courtesy lights too.

I really doubt the issue is in the fuse block.

[Jgreemo]

Thank you, I really do appreciate the guidance. I've disconnected the dome lights up near the block, along with all the other potential loads (radio, lighter, horn switch and relay) so it seems that the issue is between the block and the dash. I'm going back through the wires again this weekend and hopefully I'll find it. Sounds like fuse blocks themselves are not on the list.

[DmaxMaverick]

The fuse blocks are rarely ever an issue. When they are, it's usually due to some physical damage or hack-job. If it appears intact and absent a (man-made) rat's nest, it's likely OK.

[Jgreemo]

So it looks like a bad splice in the red power wire up under the dash. I removed the wire wrap as it entered up under the dash and the red wire had worn through some electrical tape (damn sticky mess) and was exposed. Not 100% sure why it was shorting that particular circuit but I repaired it properly and it's working fine now. Hopefully that's it and onto the next project. Thanks all!