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Troubleshooting Tips - Lighting/Wiring

A Few Helpful Tips To Get You Started:
  • Make sure all of the connections are clean and secure, and the wires are correctly plugged in on each side like the taillight images below.

Drivers_side.jpgFig.1.jpg

Passenger_side_image.jpg Fig.2.jpg


  • A multi-meter or 12-volt light probe will help you track down the root of the problem.


  • Periodically coat connections with a dielectric silicone which can help prevent corrosion.


  • At least twice a year, inspect your trailer’s electrical system. Check the insulation on the wire for nicks that could lead to corrosion or shorts. Make sure there are no loose wires so they don't hang down where they can snag.


TROUBLESHOOTING SCENARIOS

Caution: Be sure to unplug the trailer lights before going any further. 

SCENARIO #1 - Total Loss Of Lights On The Trailer

This usually means that either the tow vehicle's light system has failed or the connection between trailer and tow vehicle is suspect.  

 

  • First check the vehicle itself. If the vehicle's lights don't work, look for a blown fuse in the fuse panel (either below the dash or under the hood).


  • If the vehicle's lights are working, check for power in each port of the vehicle's trailer plug by using a multimeter to probe each terminal while a helper switches lights on and off.


  • If the connector is not delivering power, check for proper ground. A broken ground wire, excessive paint, or corrosion between the ground wire and its' connection point on the vehicle’s frame could be the problem.


  • If the bolt that connects the ground to the frame is touching bare metal, but you still don’t have power to the connector, either the connections with the tow vehicle’s wiring harness are bad or the connector is faulty. In this case, check all the connections on the vehicle’s wiring harness (call us 1-800-337-2327 for further assistance on this).

 

SCENARIO #2 - Only Some Of The Trailer Lights Are Working

The best thing to do is use a test light or multimeter to check any wires that lead to a failed light. This allows you to determine if the wire itself is delivering power. 

 

  • Check the light bulb to see if it is burnt, blackened, or has a broken filament.


  • If the bulb looks good, use steel wool to clean the lead contacts and brass casing (lead contacts need to touch the brass plates).

  • Reinstall the bulb, reconnect the trailer wiring harness and see if the lights work.

  • If the wire is delivering power, it is highly likely that the light fixture’s individual ground is the problem. To ensure a solid ground:

1) Check the white wire

2) Check the connection to the vehicle

3) Ensure the bolts on the back of the taillight are clean and free of corrosion

  • Remember you can’t get a good ground connection through paint or rust. Grind down to bare, shiny metal to ensure a solid ground connection.

  • CAUTION: If bayonet style bulbs with the lugs are inserted in the wrong slots, the bulbs will be loose resulting in lights that are dim and intermittent


  • If the dim/bright operation is out of phase, you know the bulb has been reversed in its fixture.

If you have any other questions or need further assistance, please call SnowBear Limited's Customer Service Team at 1-800-337-2327. We're here to help!