Another wiring/ground issue with rear tail light

[Indyharleyguy]

Hi All, My 1984 M1009 has a left rear tail light issue. At first the whole left tail light, brake light and turn signal light didn't work. I found the ground wire has rusted off. I fixed that and now have a brake light and turn signal. But the left tail light still didn't work. I thought ok even the bulb looked OK must be a bulb issue. My right tail light worked OK so I swapped them. Same problem, left tail light not working and right tail light working. I figure there must be another ground wire not working but not sure where to find it.
All other lights all the way around the truck work just fine.
Oh and the inside of the left tail light socket seems to be ok. At least I don't see any rust or corrosion anywhere in it.


Wanted to see if anyone had some thoughts.
Thanks

 

[Barrman]

Do you have a test light or volt meter? Since the tail light and brake light share an 1157 bulb housing. You can remove the bulb and check for voltage on the two leads at the bottom of the socket. If you have voltage there, then ground is still your issue. No voltage, then you get to do what the manual calls "chase wiring." Follow the wire to where the left/right split is on the driver side frame rail next to the fuel tank. Since the right side is working, the problem has to be between the split and the bulb housing.

 

[Indyharleyguy]

Do you have a test light or volt meter? Since the tail light and brake light share an 1157 bulb housing. You can remove the bulb and check for voltage on the two leads at the bottom of the socket. If you have voltage there, then ground is still your issue. No voltage, then you get to do what the manual calls "chase wiring." Follow the wire to where the left/right split is on the driver side frame rail next to the fuel tank. Since the right side is working, the problem has to be between the split and the bulb housing.

Hi OK thanks. I'll test with my voltage meter and see what it tells me.

 

[ezgn]

Hi All, My 1984 M1009 has a left rear tail light issue. At first the whole left tail light, brake light and turn signal light didn't work. I found the ground wire has rusted off. I fixed that and now have a brake light and turn signal. But the left tail light still didn't work. I thought ok even the bulb looked OK must be a bulb issue. My right tail light worked OK so I swapped them. Same problem, left tail light not working and right tail light working. I figure there must be another ground wire not working but not sure where to find it.
All other lights all the way around the truck work just fine.
Oh and the inside of the left tail light socket seems to be ok. At least I don't see any rust or corrosion anywhere in it.


Wanted to see if anyone had some thoughts.
Thanks

https://www.steelsoldiers.com/threads/cucv-electrical-ground-locations.120289/

 

[Mullaney]

Hi OK thanks. I'll test with my voltage meter and see what it tells me.

.
A little time spent under the dash (beside the E-Brake) is a ground in the thread that @ezgn referred you to. That ground in particular, a wire brush (small - tooth brush sized), and a tube of Anti-Oxidation Paste will make the entire truck happier. Read the link to find the others. Another option is a spray version of "AntiOx" that will help clean things up...

 

[ssdvc]

Just FYSA, I had the same issue and it turned out to be a bad bulb socket. I cleaned it and did some "tightening" up of the socket and all was right with the world once again.

 

[Indyharleyguy]

.
A little time spent under the dash (beside the E-Brake) is a ground in the thread that @ezgn referred you to. That ground in particular, a wire brush (small - tooth brush sized), and a tube of Anti-Oxidation Paste will make the entire truck happier. Read the link to find the others. Another option is a spray version of "AntiOx" that will help clean things up...

OK I'll check it out too. Thanks

 

[Indyharleyguy]

Just FYSA, I had the same issue and it turned out to be a bad bulb socket. I cleaned it and did some "tightening" up of the socket and all was right with the world once again.

OK Thanks I'll check that out.