Troubleshooting Weak Trailer Brakes That Won't Lock Up with Override Lever of Controller Slid
Question:
I can not get the brakes to lock up with the manual slide override. I max it out @ 12 volts but the trailer brakes barely have any stopping power. I tried setting them up just as the instructions said but they will not work.
asked by: George M
Expert Reply:
This could be a magnet wiring problem. It is unlikely that the magnets are bad on newer assemblies, but if the wiring is not properly connected, it could cause problems. Check to see that the magnets are properly grounded to a clean, bare metal surface free of corrosion. A bad ground would not allow the circuit to be complete and lead to the brakes not performing like they should.
I also recommend checking the trailer side connector ground and the vehicle side connector ground.
Another possibility is that the brakes are out of adjustment. You want to adjust the assemblies so that there is a light drag when the wheel is turned. To see how this is done check out the video I attached. Fast forward to the 4:30 mark.
I also attached an FAQ article on troubleshooting brake magnets.
Robby
6/6/2020
I been having problem with a brand new set of brakes . They are adjusted all the way up and will not stop trailer . I have battery voltage at the new magnet assembly . All wiring is new and extra good ground is has been added . The only thing that is not new is the drums . The drum were not scored and smooth . Could the new magnet brake assembles not expanding enough for the old drums ?
Flanagan
7/10/2020
I too have lost my trailer brakes I greased the ball hitch recently Could this be the problem ? Wiring all checks out
Chris R.
7/14/2020
Harold
7/9/2024
I'm surprised no one said anything about the voltage. Many of these cheaper brake controllers won't even get up to 12 full volts therefore will never lock up the brakes. If you only have 9.5 volts the trailer brakes will shut a little bit but they're better going to close and lock up all the way unless you have a full 12 volts and most likely when people buy a brake controller they go cheap and they get cheap. They need to put out a full 12 volts before the brakes will ever Fully lock up. I just had this problem. It works only put out 9.56 volts on the top end and lowering it was a joke
Jameson C.
8/7/2024
Product Page this Question was Asked From
Tekonsha Primus IQ Trailer Brake Controller - Up to 3 Axles - Proportional
- Trailer Brake Controller
- Proportional Controller
- Electric
- Automatic Leveling
- Under-Dash Box
- Dash Mount
- Up to 3 Axles
- LED Display
- Up to 90 Degrees
- Tekonsha
more information >
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on Trailer Brake Controller
Jason H.
4/27/2020
we just installed new brake assemblies on all four corners of a 20 flatbed trailer. All wiring and contacts are good. No grease. Nothing. When we run the trailer gain up to 10, the trailer BARELY holds the 5.7L gas pickup truck. We run across gravel and slam the controller on at 10 and the wheels refuse to lock. What could be wrong ?????