Troubleshooting Trailer Running Light Issue Connected to 2018 Ram 1500

Question:

question-290123 Have the same problem on my 2018 ram 1500 just went on the way back from the lake with the boat u think it would be the same fuse

asked by: Grant

Expert Reply:

It is possible the running light fuse for your trailer blew and that is the F29 blue 20 amp fuse, although it may be a different color if it has already been replaced. Since the lights went out on the trip, it very well could alternatively be a ground wire issue on your trailer. You can test for power on your 7-way pin using a circuit tester like # PTW2993 and that will tell you if you have a vehicle side issue or a trailer side issue. If it is the vehicle side, and the fuses check out, then use the circuit tester behind the 7-way to see if the connector has simply gone bad internally and can be replaced with # PK11893 or # HM40975.

if it is trailer side, then the main ground and the ground which can be through mounting hardware of each tail light should be checked. You want make sure you have a clean metal to metal connection so I recommend removing each ground/mount connection, using sand paper to make sure it is clean, and then reattaching. If that doesn't solve the issue you will need to trace the wires for that function looking for connection issues, missing insulation, and breaks. If you can't find anything then you will need to test with # PTW2993 to see where the power is discontinued and replace that section of wire.

I've attached a couple articles to assist with diagrams/locations.

expert reply by: Jason S