Post by jmurphy on Aug 30, 2014 11:47:28 GMT -4
I recently picked up a trailer with brakes. My tow rig is 2006 Pathfinder SE and came with OEM 7-way trailer wiring. All I had to do was buy a couple short connecting harnesses, a relay, a brake controller, and a 7-way vehicle connector and I'm good to go.
Here's the problem: I have 12V on the blue brake wire whenever vehicle power is on. It will light a test light and shows 12V on the meter. 12V is present with and without the brake controller connected. With the vehicle off no voltage is present.
The Pathfinder has 3 relays for towing. 2 to control the lights and 1 (which I added in an empty socket) to control brakes. When you turn the key on you can hear the brake control relay immediately close. Like I mentioned this happens whether or not the electronic brake controller is actually connected.
So.... To trouble-shoot I'm looking for the source of the signal that's closing the brake control relay? Yes?
edit: No. Finally found the right wiring diagrams. The power to the trailer brakes does not go through any of the factory relays. Factory harness should supply 12V to controller and blue brake wire should only connect to controller and 7-way plug. Nothing else... More pin-outs to check now.
And the cause is: Factory harness and "vehicle specific" after-market parts don't play together. Wires are all mixed up. Brake ended up as black wire on terminal 5, instead of blue on terminal 2. Not sure what else is wrong... Now to decide whether to probe out and move wires or just return the parts and buy OEM ($$)
..sigh...
Jonathan
Here's the problem: I have 12V on the blue brake wire whenever vehicle power is on. It will light a test light and shows 12V on the meter. 12V is present with and without the brake controller connected. With the vehicle off no voltage is present.
The Pathfinder has 3 relays for towing. 2 to control the lights and 1 (which I added in an empty socket) to control brakes. When you turn the key on you can hear the brake control relay immediately close. Like I mentioned this happens whether or not the electronic brake controller is actually connected.
So.... To trouble-shoot I'm looking for the source of the signal that's closing the brake control relay? Yes?
edit: No. Finally found the right wiring diagrams. The power to the trailer brakes does not go through any of the factory relays. Factory harness should supply 12V to controller and blue brake wire should only connect to controller and 7-way plug. Nothing else... More pin-outs to check now.
And the cause is: Factory harness and "vehicle specific" after-market parts don't play together. Wires are all mixed up. Brake ended up as black wire on terminal 5, instead of blue on terminal 2. Not sure what else is wrong... Now to decide whether to probe out and move wires or just return the parts and buy OEM ($$)
..sigh...
Jonathan
