Grounding Woe's

For the last two months, I have been steady working on recently purchased M1009. Fortunately, I have my M1008 to use as a guide. Without it, I would have been lost long ago. One of the bug-a-boo's I have been trying to deal with is the loss of some of my grounds which was causing havoc with my headlights, marker lights, and turn signals. I have been trying to trace and repair the problems for the last three days. Naturally, I unbolted/unscrewed the vehicle grounding points, used my wire brush to clean the area's, sanded the grounding wire eyelets, and reinstalled everything. Unfortunately, it didn't make a difference. My marker lights were still poorly lit and the turn signals were not functional. I was ready to beat my head into a wall. By trying a wide variety of tactics and checking each and every wire that is in the front of the truck, I finally figured out where the problems were located - both of the 1157 marker sockets in the front were broken. While the bulbs fit properly and were easily locked into place, the ground tabs that are supposed to extend down into the bulb sockets were broken off and missing. In the attached picture, the socket on the left is damaged. It is missing the grounding tab that you can clearly see in the socket on the right side of the pic. I purchased a replacement socket from O'Reilly Auto but was unimpressed with it as it wouldn't lock into place on the plastic lens. I then went to NAPA (bringing the plastic lens) to see if they had replacement sockets. Fortunately, they did have the sockets and they fit the lens really well. The NAPA part number is LS6461. I had to replace both sockets. Each socket was about $11.00. These parts fit the Blazer really well. Unfortunately, each socket came with a BLACK, BROWN, and YELLOW wire. The DS socket on the CUCV is Black, Brown, and Lt Blue while the PS side is Black, Brown, and Dk Blue. I clipped out the old sockets and soldered/heat shrinked in the new sockets. It was an inexpensive and easy fix. Hopefully, this post will help someone else.

Glad that you found the problem. That is the reason I always suggest to look at the bulbs and sockets over closely.

Water seepage is the primary reason for socket failures. Look at the lens gaskets close as when they crack or are missing water gets blown in when traveling and from idle moisture.

There is also a socket gasket that after time gets bad and never gets replaced. Does your new sockets have them?

When walking through salvage yards I will check out the sockets on the front and back of chevy trucks for real good ones to keep for replacements. I believe that the originals are better than the new made. I have not bought a bulb or fuse in 30 years.

Nice detective work.

That's what dielectric grease is made for. Fill those sockets before putting in a bulb. Same with your ground connections.


By the way, please learn to use paragraphs. Those massive blocks of text are hard on the eyes.

cucvmule said:

Glad that you found the problem. That is the reason I always suggest to look at the bulbs and sockets over closely.

Water seepage is the primary reason for socket failures. Look at the lens gaskets close as when they crack or are missing water gets blown in when traveling and from idle moisture.

There is also a socket gasket that after time gets bad and never gets replaced. Does your new sockets have them?

When walking through salvage yards I will check out the sockets on the front and back of chevy trucks for real good ones to keep for replacements. I believe that the originals are better than the new made. I have not bought a bulb or fuse in 30 years.

Click to expand...

Yes, the new sockets came with the foamy style gaskets. I would have preferred to get replacement sockets from a scrap yard as well so the colors would match, but unfortunately I don't have a scrap yard within 60 miles of my location. The few that I can travel to will not let part hunters into the yard. They make you tell them what you want, and then wait while they try to locate the parts themselves. I really miss traveling through the yards looking at stuff and getting ideas.

MarcusOReallyus said:

Nice detective work.

That's what dielectric grease is made for. Fill those sockets before putting in a bulb. Same with your ground connections.


By the way, please learn to use paragraphs. Those massive blocks of text are hard on the eyes.

Click to expand...

Sorry for the block size. I will endeavor to do better in the future...