Finding Fuse and Relay Locations for Tow Package Wiring on a 2005 Ford F-150

Updated 04/21/2020 | Published 10/13/2012

Question:

I have a 2005 F150 4x4 short bed with extended cab truck with the factory tow package installed. The four pin plug does not have any power on the tail light circuit. The turn signals and brake lights are fine. My neighbor has the same problem with his 150 as well. Can you direct me where to check for fuses and relays that are in this circuit?

asked by: Dudley F

Expert Reply:

If you look at the owners manual for the truck and/or the legend on the power distribution box lid it will tell you the locations of the fuses/relays that are related to the tow package wiring. I found an online version of the owners manual and the fuse/relay section starts on page 224.

For fuses it looks like the trailer tow parking lamp fuse is in location 10 and the relay is location R201.

expert reply by: Michael H

Billy F.

4/19/2020

I just purchased a new utility trailer I have a 2007 ford f150. The issue I have is when the running lights are on the right turn signal sees not blink on the trailer light. At first the running lights would not work on trailer replaced the fuse they started working but the blinker does not blink. What to look for next

Chris R.

4/21/2020

Does the right turn signal blink when the running lights are NOT on? If so, this is a pretty common symptom of a bad/weak ground. I would make sure that right light assembly is securely grounded to the trailer frame - whether it grounds through a dedicated wire or through its mounting hardware. The metal it's contacting needs to be completely clean and free of debris or corrosion. Also check the main harness ground on the trailer. If this doesn't help just let me know.