Hi--we have a 2003 Expedition with a tow package. I bought a Reese electric brake control for a trailer and am putting it in. The ford kit that came with the car has the harness and the two relays. The schematic that came with the kit shows the relay box under the hood--ours is on the passenger side. The problem I am having is that I can't tell which relays to replace. The actual box that is diagramed in the owner's manual doesn't match the box from the kit schematic. I know that I have to replace the Trailer Tow Backup Relay (the smaller one) and the Trailer Tow Battery Charge Relay (the larger)..but when I look at my owner's manual, the relay number R05 should go---------but I can't find the other one--any help?????????????????

 

There are a couple of brake controllers out there that have a reputation that is far better than the Reese brake controller (The Tekonsha Prodigy and Jordon Ultima). I have the Prodigy, which I was able to buy a $10 wiring harness for that very simply just plugs into the brake controller and a plug for a brake controller underneath the driver's side dash on the right side. It was literally plug and play, took 15 mins to mount and plug in. Set in and forget it.

http://www.tekonsha.com/prodig.html

 

I had a very similar problem with my '00 F150. I remember the drawing and directions that Ford provided were not very user friendly. My suggestion is to check again under the hood for a fuse/relay box. The relays that are provided in the kit go in the box under the hood, not the one mounted to the passenger side. That's how it was for my '00 anyway. I distinctly remember having a problem with where to put those d@&n relays! Good luck.

 

If you look uner the hood you should find a fuse box, right in front of that box is a little box that is most likely taped closed. Remove the tape and the cover and your relay's go in there. The size of the relay box is approx. 2"X4".

Good luck Toyman

 

I think the 02' had the box under the hood. My 03' expy box is in front passenger sidewall.