2021 GC Long Altitude

[Jactan]

I have a 2021 GC Altitude long I have a full OEM trailer package in my Jeep GC long. Recently my trailer running lights stop working all my other trailer lights work fine brake turn etc. I have checked the fuses under the seat hood and dashboard all were good. I even went under the truck and check the power going into the factory plugs all have power except the brown wire for the running lights. I downloaded the factory diagram apparently there a relay and ground attached to the harness. But it looks like I may need to disassemble half the interior to get to it anyone experience this or can help. Joe Dolci

 

[RichSNJ]

I have a 2021 GC Altitude long I have a full OEM trailer package in my Jeep GC long. Recently my trailer running lights stop working all my other trailer lights work fine brake turn etc. I have checked the fuses under the seat hood and dashboard all were good. I even went under the truck and check the power going into the factory plugs all have power except the brown wire for the running lights. I downloaded the factory diagram apparently there a relay and ground attached to the harness. But it looks like I may need to disassemble half the interior to get to it anyone experience this or can help. Joe Dolci

I had a similar issue with my WK2 and it was one of the fuses under the hood. Unfortunately the fuse blocks are completely different now and I've never found one that sounded like it was for the trailer plug in the user manual, but I can only assume they are there. Did you check all the fuses in all the blocks, or just ones that sounded close? Maybe since the trailer package is an option they don't list it in the manual. If you have the factory wiring diagram, does it show the fusing and if so, specifically which fuse box it's in?

For my own use, where did you download the diagram from? I would love to see / get wiring diagrams...

 

[Jactan]

I had a similar issue with my WK2 and it was one of the fuses under the hood. Unfortunately the fuse blocks are completely different now and I've never found one that sounded like it was for the trailer plug in the user manual, but I can only assume they are there. Did you check all the fuses in all the blocks, or just ones that sounded close? Maybe since the trailer package is an option they don't list it in the manual. If you have the factory wiring diagram, does it show the fusing and if so, specifically which fuse box it's in?

For my own use, where did you download the diagram from? I would love to see / get wiring diagrams...

I tested every single fuse in all three fuse blocks.

 

[eleceng1979]

Because you have an oem trailer package it requires factory/dealer software update to be enabled. Due to the recent software updates others are talking about, it is plausible that this update possibly turned the clearance lights off/messed it up. Only a dealer could scan and tell if enabled/fix. If all other lights function, then that would seem to indicate trailer ground is good. If it worked prior and you haven’t changed trailer wiring/light bulbs, Jeep is to blame.

 

[Jactan]

Because you have an oem trailer package it requires factory/dealer software update to be enabled. Due to the recent software updates others are talking about, it is plausible that this update possibly turned the clearance lights off/messed it up. Only a dealer could scan and tell if enabled/fix. If all other lights function, then that would seem to indicate trailer ground is good. If it worked prior and you haven’t changed trailer wiring/light bulbs, Jeep is to blame.

I took the truck to Jeep and after 4 days they told me the problem was fixed blown fuse. I went out and tested the wiring and guess what running lights still not working but they did change the battery and fuse box under the seat for other issues that I was having. I took the truck home and notified the service writer the truck still had issues with the trailer lights. So, I decided to dive into this even deeper and found the trailer light relay in the wheel well under the wheel cover. I'm positive at this point that's the problem is the trailer light module because the grounds and other relays are working properly. I didn't bother to return it to the dealer and purchased a new module which is coming Friday. I will keep u posted on the results I hope this helps anyone else with this problem. Joe

 

[Jactan]

So today I received the Mopar light module part 68379332AA and installed it and happy to say all my trailer lights are functioning properly. I'm going to try and recover the cost from Jeep for the module. I believe the problem originated from a short in my box which was causing problems that have since been corrected. Jeep replaced fuse box and battery last time it was in for service. I hope this helps other with this problem.