Engine/Transmission (1994 - 1998) Brake Controller Problems?

[jglasgow]

I have a 96 12 Valve with 5 speed, the brake controller was working fine 2 weeks ago and now it does not control the trailor brakes, the lights and signals all still work the is just no power on the acutal brake wire. I have checked all of the fuses in the fuse panel and they are all fine. I have scanned it with the modis scanner and it has no codes. I have replaced the brake controller and harness to the factory plug and still have the same problem. Any help would be appreciated, thanks a lot, John.

 

[JimBob24]

I know you said you checked all the fuses, but be sure to check the one marked CHMSL. (Center-high-mounted-stop-light). On my '97 I had the same situation and this fuse was the problem. I assume it is the same on the '96. This is where the sense voltage to the brake controller comes from.



Jim

 

[Stark_Ent9802]

I could still be the trailer even though the light and signals are working. I'd say if you can, try another trailer with your truck and have another truck try your trailer.

 

[tgordon]

Is the controler responding as you apply the brakes?



If you use the manual override can you engauge the brakes on the trailer?



Just a couple simple things to look at and search before you go crawling around.

 

[jglasgow]

I have tried using the manual override switch on the controller and it works fine, I will check that fuse again today to make sure, thanks.

 

[jglasgow]

The Center Brakelight Is Working and I checked all the Fuses again, no problems.

The controller is not responding when you apply the brakes but the manual switch will.

Any more suggestions?

Thanks,

John

 

[hsmith]

Most controllers get their signal from the current leaving the brake light switch. I would look there, even the switch itself.

 

[jglasgow]

Most controllers get their signal from the current leaving the brake light switch. I would look there, even the switch itself.

I tested the brake light switch with the plunger all the way out at terminals 5 & 6 and had continuity, I then pushed the plunger all the way in and tested terminals 1 & 2 and had continuity. I think at this point I will get a new brake light switch and try it.

Thanks again,

John

 

[jglasgow]

New Brake switch made no change.

John

 

[tgordon]

I am guessing you have the plug in under the dash. Have you checked to see if there is signal going to the switch telling it to engauge the trailer brakes? Maybe there is some corrosion in the plug not allowing good contact? I am thinking a bad wire/conection between the switch and the controler.

 

[jglasgow]

I checked the wires at the factory brake controller harness and found out that the red wire which is white with tan stripe on the factory plug has no voltage. It is supposed to be the stoplight wire and should get voltage when pressing the brakes but it has no voltage at all.

 

[jglasgow]

Fixed

The Center Pin on the larger connector behind the driver side tire was corroded.

Replaced the pin and everything is working fine now.

Thanks for everybodys input,

John