What Does Trailer Wiring that Has Voltage on All Pins of the 4-Way Indicate

Updated 04/22/2019 | Published 04/20/2019

Question:

When testing my lights for my trailer on my vehicle with a tester the wire coming from my car there are all hot all the time they stay lit, everyone both turn signals and brake, does that mean the T connector is bad ?

asked by: Gary K

Helpful Expert Reply:

If you have a trailer wiring harness that's putting out voltage on all of the pins all of the time it does have an internal problem and need to be replaced. The converter boxes of the wiring harnesses are designed to "sacrifice themselves" in the event of a short to prevent the short from damaging the vehicle wiring too. So first thing to do is fix the short on your trailer wiring. Look for exposed wire that could touch metal and fix as needed before replacing the wiring harness.

expert reply by: Jameson C