Troubleshooting Right Side Trailer Lights That Are Dim
Question:
I noticed that my right turn signal and rt tail light is dim on the trailer. I wanted to troubleshoot a bit further and hooked up a 4 way trailer light tester and the same dim light on the rt side. I unplugged the harness and re plugged everything and it is still dim. Any idea as to what it may be? I bought the harness from you maybe a year ago. Is it a faulty harness, dirty connections, ground? My lights are LEDs so they should both be super bright.
asked by: Adam
Expert Reply:
Since you trailer's right side turn and tail lights are dim, but still operate somewhat, the most likely cause is a bad ground at the light unit itself. If the main trailer ground were at fault this would affect both sides of the trailer so odds are that the issue is at the light assembly.
If the light uses a mounting stud for its ground remove the fixture and sand/clean the area to remove any paint, primer or grease that may be interfering with the ground connection. If the light uses a wire lead for its ground, such as # 271595, then clean the point where the ring terminal is attached.
If you have a voltmeter like # PT89ZR you can test the output of the vehicle 4-pole harness (with the trailer disconnected) to see if the voltage is the same on both left and right sides of the 4-pole. Please refer to the linked photo and article for more on testing.
Products Referenced in This Question
Wraparound LED Tail Light for Trailers Over 80" - 8 Function - Submersible - Red - Driver
- Trailer Lights
- Tail Lights
- License Plate
- Rear Clearance
- Rear Reflector
- Side Marker
- Side Reflector
- Stop/Turn/Tail
- Rectangle
- Surface Mount
- Submersible Lights
- LED Light
- 7-L x 3-3/4W Inch
- Red
- Wesbar
more information >
Digital Multimeter with 42" Long Test Leads - LED Display
- Electrical Tools
- Testers
- Multimeter
- Yellow
- Performance Tool
more information >
Product Page this Question was Asked From
T-One Vehicle Wiring Harness with 4-Pole Flat Trailer Connector
- Custom Fit Vehicle Wiring
- Trailer Hitch Wiring
- Converter
- Custom Fit
- 4 Flat
- Tekonsha
more information >
Featured Help Information
Instructions
Miscellaneous Media
Continue Researching
- Shop: Americana Trailer Wheel Lug Nut - Chrome Plated - 1/2"-20
- Search Results: 1/2 x 20 lug nuts
- Shop: Hydrapro Alpha G-1600 Electric Over Hydraulic Actuator for Disc Brakes - 1,600 psi
- Search Results: lug nuts
- Shop: Kodiak 13" Rotor - 8 on 6-1/2 - Raw Finish - 1/2" Bolts - 7,000 lbs
- Shop: Kodiak 13" Rotor - 8 on 6-1/2 - Dacromet - 1/2" Bolts - 7,000 lbs
- Shop: DeeMaxx Trailer Idler Hub for 7,000-lb Axles - 8 on 6-1/2 - Galvanized
- Shop: Americana Trailer Wheel Lug Nut - 7/8" Diameter - Stainless Steel - 1/2" - 20
- Shop: Chrome Trailer Wheel Lug Nut - 1/2" - Qty 1
- Video: Dexter Axle Brake Actuator - Electric-Hydraulic Brake Actuator - K71-651 Review
- Search Results: boat trailer master cylinder
- Q&A: Troubleshooting Leaking After Dexter EOH Actuator for Disc Brakes 1600 PSI Installation
- Search Results: boat trailer brakes
- Video: Optronics Trailer Lights - Tail Lights - STL211RCB Review
- Video: Optronics Square LED Trailer Tail Light Installation
- Article: Troubleshooting 4 and 5-Way Wiring Installations
- Article: Brake Controller 7- and 4-Way Installation Kit (ETBC7)
- Q&A: Troubleshooting Left Turn Signal Light on Trailer that Is Dim But Not With Brake Lights
- Q&A: Trailer Running Lights Do Not Work but Brake Lights and Turn Signals Do Work
- Q&A: Troubleshooting 3 Malfunctioning Trailer Marker Lights # MC53RB on 2007 PJ Flat Bed Trailer
- Q&A: How to Choose a Grease Cap for a Trailer that Does Not Have Grease Caps
- Video: Dexter Replacement EZ Lube Drive-In Grease Cap Review
- Video: Review of TruRyde Trailer Bearings Races Seals Caps - Grease Cap with Plug - TRU66FR
- Search Results: harness
- Q&A: Should 12 Volt Hot Lead on 7-Way Trailer Connector Be Hot All the Time, WIll it Drain the Battery
- Q&A: Can I Charge My Trailer Battery Using 7-Way Trailer Connector on Truck
- Search Results: 16 gauge wire
- Search Results: y~adapter
- Article: Brake Controller Installation: Starting from Scratch