Posted 2010-10-11 9:57 AM (#125644) Subject: Trailer braking question
Veteran
Posts: 150 Location: Le Claire IA
My Prodigy works when I use the manual knob but doesn't when I use the brake pedal. I've set it to just under lock-up. Works perfect manually and I'd be happy but I'm not going to keep braking this way. The service dep. said my brakes were fine when I had the bearings packed. The wiring to the brakes has been updated and each is grounded. What would cause this?
Posted 2010-10-12 10:34 AM (#125678 - in reply to #125644) Subject: RE: Trailer braking question
Veteran
Posts: 150 Location: Le Claire IA
The 3rd brake is not. The oil change shop said it has a short....hmmmm, I had forgotten that, but the left and right come on, on the truck and trailer.
I have the controller wiring harness with plugs at both ends so I could just plug in to simplify. ha ha ha...I contacted Tekonsha after watching several installation videos and they've sent me a Technical bulletin that GM made some pin changes in 2003, I have a 2004. I have several harnesess since I had an Envoy I thought wasn't working and the harness that needed to be wired was in the truck from the previous owner. I just happened to look at those pins last night and saw they were different. I got the bulletin this morning and it has instructions on how to change the pins. I hope this is the problem and will fix it. The contoller was also going into sleep mode and I have to move the manual slide to "wake" it up, or will this 3rd brake light mess up everything? Thank you.
Posted 2010-10-12 9:20 PM (#125712 - in reply to #125644) Subject: RE: Trailer braking question
Expert
Posts: 1416 Location: sc
Pretty sure the 3rd brake light on a GM has to be working for power to the red wire. The pin location changes from the 03 to 04 involve the parking lights, IIRC.
Posted 2010-10-12 9:42 PM (#125713 - in reply to #125644) Subject: RE: Trailer braking question
Expert
Posts: 1416 Location: sc
Just went and put a test light on the red wire with the 3rd brake light fuse pulled.........no power. Mine is a 05, but I doubt your 04 is any different.