Troubleshooting Trailer Brakes That are not Functioning Properly

Question:

After the blowout, the brakes would grab and very slow to release. This affected truck and trailer brakes. We are talking hot trying to move. Made it to the campground and spliced the wires back together. No difference with the brakes at all. The truck worked ok as long as it wasnt hooked to the trailer. Cut the blue wire coming out of CURT 51140 TriFlex Electric Trailer Brake Controller. All the trailer lights and signals worked ok on the way home. We used the truck brakes only very carefully for the trip home. Would a short cause anything like this. Any advice as to where to start? Thanks

asked by: John L

Helpful Expert Reply:

This sounds like it could be one or two things. A short could definitely be causing the issue, but it may also be a ground problem as well.

To start, reconnect the blue wire to the brake controller. This will take two people but using something like the Circuit Tester # PTW2993 you will need someone to run the manual override on the TriFlex # C24VV while checking the output on the 5 o'clock position on your 7 Way. This should be putting out 12 volts, or very close to it. When the manual override is released, it should then drop back down to zero. If this is the case, odds are the controller has gone bad and will need to be replaced if you have the factory installed 7 Way plug. If the vehicle was not originally set up to have the 7 Way and brake controller, you will need to check your ground connection. These can go bad over time and will need to be re-grounded to bare metal. Once done, retest the manual override. If it still isn't going from 12 volts to zero volts, the controller definitely needs to be replaced. On the other hand, if it is going from 12 volts to zero in either of these situations, the controller and or vehicle will not be the problem.

If this is the case, you most likely have a ground issue on the trailer. A bad ground can cause all sorts of different issues, and this does sound like what is going on. You will need to make sure all the grounds are connected to bare metal that is not aluminum. You should also check to see if each brake has its own separate ground as well. Some manufacturers do not do this and will combine several grounds in to one source. Granted most of the time this is fine, it is better to have a ground for each, however. Once these are checked and or re-grounded, hook up to the truck and do a short test run to see if it is still going on. With all this done, you should be good to go.

It should also be noted that the Curt # C24VV does have a Lifetime Warranty, so if it is the controller that has gone bad it should be covered. If it was ordered through etrailer.com, give us a call at 1-800-298-8924 and we can get you the warranty information. If it was ordered through another company, you will need to contact them for said warranty info.

If neither of these fix your issue, however, let me know and we can try something else to get you up an running properly.