Running Lights Not Working

[FatBuddhaBoo]

All was fine until the other day...here's my issue:

Noted Monday morning that my dash lights were out while driving to work and thus couldn't read my speed, etc. Wife was in her car behind me and called to inform me I had no tail lights but brake lights and rear turn signals work. It was dark, so yes the headlights were on. Got to work and checked that the front turn signals work as well and confirmed that the rear tail lights were not working. After work I checked all the fuses and found none bad. Inspected all the bulbs and again all were good (having recently replaced all bulbs) Took dash apart, cleaned all headlight switch connections, replaced all fuses but still the same. Grounds are tight under hood compartment. Took headlight switch out and pulled it apart; found one of the nubs inside the switch severely worn down, so figured it wasn't making contact. Replaced switch today with brand new one and still the same issues.

I can jumper from the Orange/black wire (#1 on the switch harness) to the other connections which results in the taillights coming on, dash/gauge lights coming on, etc. But once the headlight switch is installed I only get headlights. I'm thinking if it were a ground or fuse issue jumping the switch positions would not make the lights work either, which leads me to believe it could be related to the black out lights. Additionally, I bought the truck with the rear bumper and front grill black out lights removed, with the wires for these terminated and taped up.

I've read over at least a dozen threads as well as following the troubleshooting in the TM's but nothing seems to point to my problem. I'm now at day 4 of troubleshooting and fully intend to get this fixed today. Hoping someone here can help.

 

[dependable]

Sounds like you know what you are doing and have tried the obvious repairs. I would still suspect a ground problem somewhere. Is the ground wire under dash by parking brake handle hooked up? Has anyone messed with junction block between fuse box and fire wall? There could be a bad connection there, but usually dies not happen if someone has not messed with it. Good luck, I know how frustrating it can be.

 

[FatBuddhaBoo]

Sounds like you know what you are doing and have tried the obvious repairs. I would still suspect a ground problem somewhere. Is the ground wire under dash by parking brake handle hooked up? Has anyone messed with junction block between fuse box and fire wall? There could be a bad connection there, but usually dies not happen if someone has not messed with it. Good luck, I know how frustrating it can be.

Yeah, definitely frustrating. As much as I wanted to, did not get a chance to troubleshoot anymore today. Hopefully have it fixed this weekend, and I'll look into the items you suggested.

 

[FatBuddhaBoo]

Well, after spending countless hours on troubleshooting, I still never found any reason as to why they work when jumped directly from the hot wire but do not work when the light switch is installed. So to correct the problem, I jumped the hot wire from the Service Switch to a secondary toggle that then connects to the wires for the dash illumination and running lights. Works great. Not overly concerned at this point, as my truck is far from and never will be a restoration (that is as long as the lights keeps working this way).

 

[dependable]

A lot of GSA trucks have been 'modified' by local agency. Sounds like you have it working. Perhaps an in line fuse in your jump circuit would be good. Some point the problem will make it self obvious, there is probably a short or ground problem in there some where.

 

[MarcusOReallyus]

Perhaps an in line fuse in your jump circuit would be good.

Dem's good advice! Maybe keep some smoke where it belongs someday, instead of letting it out where it will get into mischief.

 

[salt6]

subscribed

 

[GREENMV]

I had a problem with my M1009 brake light once and it was the ground on the left front turn signal. I went through all my light sockets and replaced with new aftermarket and have not had a problem since.

 

[FatBuddhaBoo]

I had a problem with my M1009 brake light once and it was the ground on the left front turn signal. I went through all my light sockets and replaced with new aftermarket and have not had a problem since.

Perhaps that is the answer, but for now that will have to wait.

 

[primalnick]

Did you ever find the problem. I'm having the exact same problem? Everything is good except the tail lights/ dash lights. Maybe some pics of your quick repair?

 

[MarcusOReallyus]

Nick, check your grounds!