Ok so I just spent the afternoon changing the 4 pin plug on my '06 Explorer to a 7 pin plug. From doing some research I discovered that Explorers without the class III/IV tow package can be converted fairly easily to the 7 pin as most of the wires are already there - the brake controller wires are installed on all models from factory (blue wire) and obviously the signal wires are there for the 4 pin plug. So, the only wires missing are the 12v trailer battery supply, and the backup lights/auxillary.
The 12v supply terminates behind the passenger footwell from the engine compartment at a connector, so I spliced a power cable into that plug and ran it back to the 7 pin plug, following the existing trailer brake blue cable.
Now, the problem I have is that I have no power at the trailer 12v power supply in the 7 pin plug. There is a trailer battery charger relay, which seems to be working (I even swapped the relay with another to confirm it works), and a trailer battery charger 30A fuse, which hasn't blown. I pulled the trailer battery charger fuse, ran the engine, and checked for power across the terminals - I read 0.1 volts.
I don't understand why I don't have 12 volts across those terminals - does anyone have any ideas, or know how that circuit is wired?
The 12v supply terminates behind the passenger footwell from the engine compartment at a connector, so I spliced a power cable into that plug and ran it back to the 7 pin plug, following the existing trailer brake blue cable.
Now, the problem I have is that I have no power at the trailer 12v power supply in the 7 pin plug. There is a trailer battery charger relay, which seems to be working (I even swapped the relay with another to confirm it works), and a trailer battery charger 30A fuse, which hasn't blown. I pulled the trailer battery charger fuse, ran the engine, and checked for power across the terminals - I read 0.1 volts.
I don't understand why I don't have 12 volts across those terminals - does anyone have any ideas, or know how that circuit is wired?
