Troubleshooting Right Tail Light on Trailer that Stays On with Vehicle Ignition Off
Question:
Right trailor lights stay on when i turn off ignition of truck
asked by: Randy M
Expert Reply:
When a trailer's tail light remains on when the vehicle is shut off, this usually indicates some kind of short in the wiring.
I first recommend using a circuit tester like # PTW2993 to check the vehicle side connector. You will want to see if there is constant power coming from the tail light circuit on the connector (brown wire). While there, also check for any corrosion or debris inside both the vehicle and trailer side connector and simply clean out as needed.
If you are in fact receiving a signal with the lights off in the vehicle, this indicates that the issue is on the vehicle side. Check to make sure that the brown wire is securely connected to the running light wire at the rear of the vehicle. Also make sure the ground (white) wire is connected to a clean bare metal surface.
If everything checks out fine on the vehicle side and you do not receive power at the connector with the vehicle off, then the issue is most likely on the trailer side. Check to make sure all of the grounds are secure and attached to bare metal surfaces free of dirt and corrosion.
If you are unable to resolve the issue, please let me know and I will be happy to look into this further. I have also attached a troubleshooting article that you might find helpful.


John R.
8/15/2024
I am having the same problem however I am verified it’s on the truck side I have been tracing wires until no resolve on is there more than one spot between the fuse panel and the engine compartment and the rear plug above the spare tire that is connected to each other that could possibly be or shorting out

Kenny H.
11/12/2024
I have a 2024 GMC Sierra HD 3500 ultimate and the right passenger side trailer light stays on even after ignition is off and I unplug the trailer lights from the seven pin connector inside the bed of the truck and tested depends on the plug and have a constant 12 volt current coming to the green wire which is for the passenger side trailer light what could it be causing this issue is it the trailer lamp control module underneath the bed above the spare tire or what I checked all fuses all relays everything and every fuse box on this truck they're all good besides one inline fuse underneath the bed at the bumper at the back there's an inline fuse that seems to be a black and white wire the black wire has the inline fuse it goes out to trailer brake wires and when I put fuse back into the slot it pops pretty soon after will not stay in without popping but that's the only issue I found at all but I don't think it has to do it with my problem with the trailer lights because that light on the passenger side stays on so therefore the right blinker does not work or brake light so break and blinker for the passenger on the trailer does not work like it's supposed to know running no just constantly illuminated very bright
Product Page this Question was Asked From
Featured Help Information
Miscellaneous Media
Continue Researching
- Video: Review of CE Smith Single Axle Trailer Fender Mounting Brackets 1 Fender - CES54XR
- Shop: Trailer Wiring
- Shop: Karrier ST225/75R15 Radial Tire with 15" White Spoke Wheel - 6 on 5-1/2" - Load Range E
- Video: Review of Redline Galvanized Steel UShaped BoltOn Brackets Plastic Single Axle Fender - PF1135-BKT-2
- Video: Breaking Down the Fulton Single Axle Trailer Fenders with Top and Side Steps
- Search Results: boat trailer fenders
- Search Results: fender bracket
- Shop: CE Smith Single Axle Trailer Fender Mounting Brackets for 1 Fender
- Shop: Hook Probe Circuit Tester
- Q&A: How are Fulton Plastic Top and Side Step Fenders Attached to Trailer
- Search Results: st225/75r15
- Search Results: ce26098g~2
- Shop: Fulton Single Axle Trailer Fenders with Top and Side Steps - Black Plastic - 15" Wheels - Qty 2
- Q&A: Trailer LED Lights Stay on After 2016 Ford F-150 is Turned Off
- Shop: Vehicle Tow Bar Wiring
- Q&A: Troubleshooting Trailer Running Lights Staying On when Vehicle is Turned Off
- Shop: Replacement Single Axle Trailer Fender for Boat Mate Trailers - Aluminum - Qty 1
- Shop: Tandem Axle Teardrop Fenders w/ Backing Plates - 15" to 16" Wheels - Qty 2
- Shop: Tandem Axle Teardrop Trailer Fenders for Boat Trailers - Steel - 14" Wheels - Qty 2
- Article: Troubleshooting 4 and 5-Way Wiring Installations
- Q&A: Trailer Lights Stay on Once Vehicle Ignition is Shut Off
- Video: DeeMaxx Disc Brake Kit Review
- Video: DeeMaxx Disc Brake Kit Spec Review
- Q&A: Choosing Between White Painted Wheel And Galvanized Wheel For Boat Trailer
- Search Results: deemaxx disc brake kit
- Q&A: Is There Differnce Between Trailer Grease Seals 10-36 and GS-2250DL
- Q&A: Trailer Left Side Tail Light Stays Lit Up Bright All the Time
- Article: How to Install a Brake Controller on Chevrolet / GMC 1999-2006 Pickups
- Video: Conventional Ramp Door Spring for 7' Wide Enclosed Trailer Review
- Video: Roadmaster Sterling All Terrain Tow Bar Inner Arm Replacement Installation
Jimf
4/11/2024
Regarding: “Right trailer light stays on when I turn off ignition of truck”… My issue is similar - with the difference being that the right tail/running light on the trailer stays on all of the time: when connected to the truck, when not connected to the truck, when the trailer is plugged into a residential (120v) outlet, when the trailer is running off the (12v) battery, etc. If I disconnect the battery & residential outlet, it shuts off. I’ve inspected all wiring (which looks very good - the trailer is only 3 years old) with the exception of the actual plug - because it is molded directly to the wiring (doh !!!). I’m suspecting the issue might be with that - but checking for your thoughts…