Troubleshooting Trailer Lights Where All Functions Don't Work or Are Dim
Rewired trailer With new package in March - worked well. Left side wire became frayed, so spliced it, now works. Checked all fuses- all good. Problem is right side. Rt blinker, running lights, brake not working. Does have a weak but noticeable blink on emergency flasher. I reistalled main ground, tight. Does each signal indicator have a ground? Im very confused. I ran the wire on right side - no breaks or cuts- and retied the connectors- still wont work! Cant get bulb out- how do you get out? Thanks for help!
asked by: Billy B
Tail lights do have individual ground connections. This is often through the mounting hardware instead of having a separate ground wire. With a weak ground connection you may still get some function on the light without all functions working. I recommend cleaning the mounting locations to make sure you have a bare metal to metal connection. If that doesn't solve your issue I recommend tracing your wires using a circuit tester like # PTW2993 to see if there is a short which I wouldn't rule out since you already found frayed wires. If you need more help we can do further troubleshooting.
If you can't easily access the bulb, then it is likely you have a sealed unit that won't allow bulb replacement. The sealed units are designed for submersion and are water tight by design so a complete replacement would be required if the light stopped functioning. You can test the lights with a couple wires and a 12v battery.
Products Referenced in This Question
- Electrical Tools
- Circuit Tester
- Performance Tool
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