Hi Guys, First time on. Got a problem with my F350 diesel truck's breaking system. I pull a 5th wheel and last trip almost burned my breaks up coming down long hill due to having no breaks on the 5th wheel. Had a problem early on with the lack of trailer breaks and module was replaced under warranty. Bought a new module this time and it did not fix the problem! ouch$$$!!!. Have breaking power when I use the module breaks (Hand) but not when I hit the foot breaks. Have checked the system with a meter and have good voltage with hand break but not with foot breaks. Have a good meter (voltage) read with hand breaks and faint read with foot breaks applied. Also have a faint pulsing read on test light with no breaks at all just key on. I'm stumped. Any thoughts?

 

Hello Synthia and welcome to FTE.

Have you tried adjusting the gain on your TBC up to full power?

 

Thanks Stuart. We have tried turning the gain to 10 and it makes little difference. When I was pulling my 5th wheel, occasionally it would catch a bit (not enough) but this was rare. We jacked up each wheel of the 5th wheel and checked the magnets and brakes pads (shoes) and readjusted the brakes. These all checked out good. We are getting good connection between the plug and breaks. With the truck plugged up to the trailer I can use the foot brake with little or no results and it will lock up with the hand brakes So we determined that it was no problem with the trailer. We uncovered all connection to check them, taking special attention to the grounds. We are considering changing all connections to solder and shrink wrap. This will be done soon. Had someone check how much voltage was being supplied with the foot break and the manual brakes and found that while the manual brakes were giving us a full charge for the brakes, when I step on the foot brakes it was not enough charge (Voltage) to engage and increase the brakes. On further check of all wiring involved, I believe that the only thing left to check is the hydraulic transducer, which is ordered and coming. This has been going on with this truck since the first long trip that I took when the truck was fairly new. I will let you know how it works with this new plug when it arrives and I can get it in. Thanks so much for your answer/question! I'm willing to entertain most any possibility.