Troubleshooting Trailer Tail Lights Not Working When Brake/Turn Lights Work
Updated 03/05/2019 | Published 03/03/2019 >
Products Featured in This Question
Question:
HAVE SIGNAL BRAKE FLASHERS BUT NO TAIL LIGHTS HAVE NO POWER AT THE PLUG CANT FIND A BLOWN FUSE HELP
asked by: KIRBY G
Expert Reply:
Since you have brake and turn but not taillights, the issue can be a fuse, a relay, bad wiring, or a weak connection. I recommend you first start with the wiring connection by cleaning it up with some sandpaper or steel wool, and then testing the pin for power.
If you don't have power, I recommend first checking your ground connection at the trailer plug. A weak ground connection can cause some functions to work and others not to work. Next, I recommend checking your owner's manual for a fuse or relay location that has to do with trailer taillights/running lights. If there is nothing in the fuse or relay information for trailers, then I recommend tracing your wiring from that pin location back using a circuit tester like # PTW2993 probing the wire every few feet. When you find the short, replace the wire with # 16-1-1 sold by the foot and butt connectors # DW05744-5.
If you tract to a converter box or module and you test signals coming in but not coming out, then the module will need replaced.
Product Page this Question was Asked From
Featured Help Information
Miscellaneous Media
Continue Researching
- Search Results: spare tire mount
- Search Results: for tandem~axle trailers trailer fenders
- Search Results: 205/75~14 trailer tires and wheels
- Search Results: trailer wiring
- Search Results: winch stand
- Shop: CE Smith Wobble Roller for Roller Bunks - 2-1/2" Diameter - 1/2" Shaft
- Shop: Mounting Brackets for Trailer Fender - 13"/14"/15" Wheels - Galvanized Steel - Qty 2
- Shop: CE Smith U-Bolt - Stainless Steel - 3" Long x 3-1/8" Wide x 7/16" Diameter - Qty 1
- Shop: CE Smith Post-Style Guide-Ons for Boat Trailers - 75" Tall - I-Beam Clamps - 1 Pair
- Shop: CE Smith Offset Spare Tire Mount - Galvanized Steel - 4- and 5-Lug Wheels
- Shop: CE Smith Post-Style Guide-Ons for Boat Trailers - 40" Tall - White - 1 Pair
- Shop: CE Smith Winch Stand - Galvanized Steel - 30" Tall x 2" Wide
- Q&A: Trailer Running Lights Do Not Work but Brake Lights and Turn Signals Do Work
- Shop: Trailer Hitch
- Q&A: Lug Nut Torque Chart for Trailer Wheels
- Search Results: trailer hitch
- Article: Trailer Wiring Diagrams
- Search Results: trailer tires and wheels
- Q&A: What is the Difference Between a Class II and a Class III Hitch?
- Article: Brake Controller 7- and 4-Way Installation Kit (ETBC7)
- Shop: Trailer Wiring
- Video: Fifth Wheel Towing Made Simple with Daniel
- Article: How to Measure for Trailer Hitch Drop
- Q&A: What is the Difference Between a 4-Way and 7-Way Trailer Connector
- Shop: Suspension Enhancement
- Q&A: Installation Time for Blue Ox BX1128 Flat Tow Base Plate Kit for 2016 Jeep Grand Cherokee
- Article: How to Measure Your Trailer Wheel Bolt Pattern
- Video: A Look at the Power Mountain Tallboy 6 Ton Off-Road Bottle Jack with a Military Cargo Trailer
- Shop: Brake Controller
- Shop: Gooseneck Hitch





