Troubleshooting Low Voltage Output from Brake Controller
Updated 07/20/2015 | Published 07/17/2015
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Question:
Ive checked all my connections at the controller and verified the voltage - Ive got 12v coming in at black wire, 12v coming in on red with brake pedal pushed, 12v going out on blue wire when brake is pushed and when manual override is being used. At the trailer connection point on rear of vehicle I am only getting about 2.5v for trailer brakes. I have cleaned the connections on the vehicle but doesnt seem to change that I am getting low voltage. I also tried to ground directly to the vehicle instead of using the vehicle plug and it is a consistent low volatage at 2.5 volts. Ideas? Thanks
asked by: Seth
Expert Reply:
Something is obviously causing a voltage drop between the brake controller and the trailer connector. The usual culprit in this type of situation is a break in the wire or a corroded wire. Check the wiring under the truck. You should be able to trace the trailer connector wires from the back of the trailer connector up toward the front of the truck. Look for any sections that look like they may have been pinched, frayed or even eaten through. If there are any wires spliced in or quick splices, remove those connections to look for corrosion.
If everything seems to check out okay, you could bypass the factory brake output wire and run a separate wire using something like # 10-1-1. Cut the blue wire exiting the brake controller about 6 inches back, splice in the new 10 gauge wire and run it to the trailer connector. There should be a grommet in the firewall that you can use to run the wire into the engine compartment and under the truck. Be sure to avoid moving parts or parts that get hot.. Next, locate the wire that goes into the 5 o'clock pin in the trailer connector and cut it a few inches behind the trailer connector. Leave enough length to splice-in the wire from the brake controller. This will fix the problem if you are getting a 12 volt output at the brake controller.
Product Page this Question was Asked From
Dexter Electric Trailer Brake Assembly - 10" - Right Hand - 3,500 lbs
- Accessories and Parts
- Trailer Brakes
- Electric Drum Brakes
- RH
- 3500 lbs
- Brake Assembly
- Manual Adjust
- 10 x 2-1/4 Inch Drum
- Dexter
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