Will The Breakaway Switch Draw Power When Disconnected From Tow Vehicle

Question:

If I disconnect the breakaway switch when detaching from my suv, will the brake continue to energize, pull 3amps each, and drain my battery?

asked by: Bill D

Helpful Expert Reply:

When you unhook the trailer from the SUV you are not going to pull the pin of the breakaway switch to activate the trailer brakes. The only time the breakaway switch is going to pull power is if the pin is pulled from the breakaway switch which activates the brakes. The other side of your breakaway switch has a cable that attaches to the vehicle's frame or hitch while towing. Most people use a clip to attach the loop at the end of the cable to the vehicle's frame or loop it through the hitch. When it's time to unhook the trailer you just unhook the cable from the vehicle. I have attached a video for your reference.

If your breakaway switch has it's own battery it will pull power from the 12V circuit which is attached to the tow vehicle's battery while you are towing. Once you unhook the tow vehicle the breakaway switch battery will not pull power.

expert reply by: Heather A

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Bill D.

1/1/0001

If I disconnect the breakaway switch when detaching from my suv, will the brake continue to energize, pull 3amps each, and drain my battery?

Heather A.

1/23/2020

Yes, if you pull the pin from the breakaway switch and activate the trailer brakes it will drain the battery. You never want to pull the pin from the breakaway switch though unless you are testing the switch or the unfortunate incident that the trailer disconnects from the tow vehicle while towing. Otherwise, you drain the battery and it is not great for your brakes to stay locked up. When you unhook the tow vehicle you simply remove the cable that is connected to the switch from tow vehicle. I have attached a diagram that shows how breakaway switches are wired, the cable that connects to the vehicle has an arrow pointing to it. The breakaway switch does need to be wired to it's own separate battery. Normally the switches come with it's own breakaway box for a battery and some come with a charger that allows the auxiliary battery to be charged with the 12V circuit of the 7-way on the tow vehicle. Most states require a separate battery for the breakaway switch just in the case that you lose power to the trailer, the breakaway switch would still function properly if needed. I recommend to use Hopkins Engager Push-To-Test Trailer Breakaway Kit with Built-In Battery Charger - Top Load part # 20400 which has a battery box with built in charger and the breakaway switch.