Well here we go again.

The previous owner did some pretty shotty wiring for a trailer brake module that he put in. This caused my hazard lights to not work. The problem was that the constant power wire (red with white stripe wire) to the hazard light switch was not connected. The PO cut the wire to run constant power to the brake switch. I used a quick splice connector and got it hooked back up and the hazard lights work now. There also was a solid green wire that was disconnected in the steering column so I reconnected it. I don't know if there is a break somewhere further down in that wire. Another issue is that the wire other side of the brake switch is disconnected and I don't know where it goes to. I looked at the wiring diagram and I cant figure where it goes.

All that is to say that now my rear brake lights stay on constant and I don't know what to do. I pulled fuse 13 to avoid killing my batteries but I have no idea where to start.

Btw it is a 1996 Ford F250 7.3 Diesel.

Any help will be appreciated.

 

What happens when you disconnect the brake light switch?

 

You mean the BOO on the brake pedal? I unhook the power and they stay on. The other side of the switch is not even hooked up to anything. I don't know where it is supposed to go.

 

That tells me there's still some PO wiring shenanigans in play. Since it appears most of the hack work was done with the wires to the multifunction switch, I would start by disconnecting it (all connectors), and see if that turns off the lights. If it does, then I'd start reconnecting the various connectors to the MF switch until they come on again. The PO may have played footsie with the hazard circuit, the turn signal circuit or the brake light circuit, and they're all inter-related (as a read of the EVTM illustrates).

 

Okay I will have to try that.

 

If its not inside then it might be the trailer wiring. This is a good place to check out.

Trailer Wiring Diagrams | etrailer.com

 

Oh I forgot to mention too that I removed all the trailer light wiring too. I unplugged all the wiring from the connector under the back bumper