What Amperage Draw Does Brake Controller Look for on Trailer Wiring to Sense Connection
Question:
Hi, I understand that brake controllers check for a signal draw produced by the brake magnets to “recognize” a trailer is hooked up. My question is, what is the exact signal they look for? I’m making a vehicle/trailer test box. One of the functions into hook a vehicle into it and test the vehicle wiring at the plug. I have indicator lights for each of the functions except the trailer brake signal. I installed a small voltmeter in this spot. My test light shows a faint pulsing from the brake controller. But the integrated brake controller in my test vehicle doesn’t recognize a trailer to be hooked up, therefore it won’t actually power the circuit. Should I wire a resistor in line to duplicate the brake magnet resistance, telling the truck there’s a trailer? If so, what kind of resistance or rather how much?
asked by: Wade
Expert Reply:
Easiest way to fool a brake controller into thinking a trailer is connected is going to be by installing a brake magnet on the circuit as that's the "draw" it's looking for. For that you could use the part # AKBRKR-M12 and you'd be set. The minimum ohm resistance you'd want is 7.5-8.2 ohms which is the normal resistance found on a trailer with the smallest brake magnets offered. If you went the diode route that would be the size you'd need.
I attached a link to a help article that has more info on brake magnet draws as well.
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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