Brake Magnets on Trailer are Only Showing 9 Volts
Question:
I have 9 volts going to my trailer brakes 2.5 amps on each maginet it only slow it down replaced th e back 2 magnets adjusted all 4 brakes is 9 volts enough. I can hear all 4 hum.
asked by: Frank A
Expert Reply:
If your brake controller is set to the maximum output then at the magnets you should be seeing 12 volts. If you get 9 volts then the voltage drop off could be related to the wiring such as loose connections or wire that is too small or too large (we recommend 12 to 10 gauge wire depending on the application, but usually 10 such as # 10-1-1).
It could also be a weak ground. The magnets should be grounded to a clean, corrosion free bare metal surface near the magnets.
And it could be corrosion in or on the trailer or vehicle side connector. Make sure each is clean and free of corrosion inside, where the wires attach, and outside on the pins.
Sometimes breakaway system wiring can cause problems with the brakes. If your trailer has a breakaway system make sure the wiring is not damaged or pinch and is grounded properly. You can also test brake magnets by following the help article I have linked for you.
Products Referenced in This Question
Product Page this Question was Asked From
Replacement Magnet Kit for 12" Electric Trailer Brake Assemblies - 5,200 lbs to 7,000 lbs
- Accessories and Parts
- Trailer Brakes
- Electric Drum Brakes
- 5200 - 7000 lbs
- Brake Magnets
- 12 Inch
- etrailer
more information >
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