How Can I Test Trailer Lights When Truck Is Not Available?
Updated 01/28/2026 | Published 08/27/2024
Question:
How do I test the lights on my trailer when my truck is not available?
asked by: Mark E
0
Expert Reply:
Hello Mark. The best way to do that is to use a trailer end test unit (or truck in a box as we call it) like the Hopkins Tow Doctor Trailer End Test Unit # HM50928. Some trailer shops will have these units that you can use or borrow. That or find a buddy with a truck and have them hook up to the trailer really quick so you can test.
expert reply by:
Jesse M
0
Product Page this Question was Asked From
LED Trailer Fender Clearance Light - Submersible - 2 Diodes - Amber/Red - Driver or Passenger Side
- Trailer Lights
- Clearance Lights
- Marker
- Rectangle
- Surface Mount
- Submersible Lights
- LED Light
- 8-1/2L x 1-11/16W Inch
- Amber
- Red
- Optronics
more information >
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Jesse M.
1/27/2026
Hey Mark, were you able to test your trailer lights using the Tow Doctor test unit or by borrowing a truck? Knowing what worked could help others trying to check their lights without their vehicle handy.