sailerbyday
Recruit
- Joined
- Sep 17, 2017
- Messages
- 1
Have the chronic issue where brake and turn signal lights work but running lights don't. I believe I have some strange grounding issue. Here's what I've done:
1) With a multimeter, I verified that I'm seeing 12V off of the round to flat adapter plug for my 2004 Silverado.
2) With the wire harness attached to to the flatplug on the truck, I've cut (and since recrimped) the running lights wire and verified 12 volts of the trailer harness.
3) I have a 'Y" for the running lights wire that lead back to each light. I only have one light (back right) wired to the 12V brown running light wire (no side markers are hooked up). I verified I have 12 V off each end of the brown Y ends.
I have the ground wire running all the way back to the back right light mounting bracked and have the ground wire attached to the mounting bolt. I have 12 volts between the brown wire and the mounting bolt. If I discount the grounding wire (with trailer tounge still on ball, I still read 12V.
As soon as I connect the brown lead !2V wire to the light (which is mounted and now reattached to the grounding wire), the voltage instantly drops to nothing.
Is this a ground, or some weird short. I thought it might be a short so I bought a whole new light package... Same thing. Please note, the 12 running light brown wire is not hooked to anything else. THe other end of the Y is standing free (not hooked to other rear light; side markers are not hooked up).
Hearing from others that the running lights draw more amperage (although this only makes sense if both tail lights are connected and the side markers are connected), I even 'added' and ran a 2nd grounding wire (thicker gauge) back to the same rear mounting bracket; same thing.
Here's what's also strange, If i attach the positive lead of the multimeter to brown 12V lead wire and the negative terminal of the multimeter to the brown lead wire of the mounted light, I read 12 V. Isn't this strange?
I really appreciate any help. Is there a short somewhere within the light? any other things I can do to troubleshoot this with my multimeter?
1) With a multimeter, I verified that I'm seeing 12V off of the round to flat adapter plug for my 2004 Silverado.
2) With the wire harness attached to to the flatplug on the truck, I've cut (and since recrimped) the running lights wire and verified 12 volts of the trailer harness.
3) I have a 'Y" for the running lights wire that lead back to each light. I only have one light (back right) wired to the 12V brown running light wire (no side markers are hooked up). I verified I have 12 V off each end of the brown Y ends.
I have the ground wire running all the way back to the back right light mounting bracked and have the ground wire attached to the mounting bolt. I have 12 volts between the brown wire and the mounting bolt. If I discount the grounding wire (with trailer tounge still on ball, I still read 12V.
As soon as I connect the brown lead !2V wire to the light (which is mounted and now reattached to the grounding wire), the voltage instantly drops to nothing.
Is this a ground, or some weird short. I thought it might be a short so I bought a whole new light package... Same thing. Please note, the 12 running light brown wire is not hooked to anything else. THe other end of the Y is standing free (not hooked to other rear light; side markers are not hooked up).
Hearing from others that the running lights draw more amperage (although this only makes sense if both tail lights are connected and the side markers are connected), I even 'added' and ran a 2nd grounding wire (thicker gauge) back to the same rear mounting bracket; same thing.
Here's what's also strange, If i attach the positive lead of the multimeter to brown 12V lead wire and the negative terminal of the multimeter to the brown lead wire of the mounted light, I read 12 V. Isn't this strange?
I really appreciate any help. Is there a short somewhere within the light? any other things I can do to troubleshoot this with my multimeter?
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