Trailer Connector on 1998 Ford Explorer Sport has Power All the Time

Question:

Trailer has power with no power on in vehicle has aftermarket tow harness had no factory tow package wiring

asked by: Roger S

Expert Reply:

If you happen to be using Curt trailer wiring harness # C55345 on your 1998 Ford Explorer Sport then they do usually have a little bit of power all the time. It is usually enough power to dimly light incandescent trailer lights.

There are a couple of things you can do. First, you could just make sure to always leave the trailer unplugged when the vehicle is off. Or you could install a battery isolation solenoid, such as # PK5231201 in line with the power wire for the wiring harness. The solenoid wires to a 12 volt ignition source (a source that only has power when the vehicle is on such as the radio) so that it only allows power to flow back along the power wire when the vehicle is on.

The other solution is to install a different wiring harness, # 118345, which is not known to have the same problem.

expert reply by: Michael H