Testing Electric Trailer Brakes Using Direct Battery Power
Updated 06/05/2024 | Published 06/18/2018
Question:
I have heard battery charger directly to the two wires on the electric brake and no humming in the brakes still don’t work what could be wrong
asked by: Steve
Expert Reply:
You can indeed test a trailer's electric drum brakes by directly applying +12V power from a fully-charged battery.
You can apply this power to the hot contact on the trailer's plug (see photo please) or to an individual brake assembly's two wires. With a well-charged battery delivering power you should hear gentle humming from the brake magnets and feel resistance as you try to rotate the hub.
Please note that a battery CHARGER like # CTEK56353 cannot be used to do this test. You need a fully-charged 12V battery to do it. If you are using a fully-charged battery for testing and you have no response from the brake to this full battery power input then check the main ground wire on the trailer for a loose or corroded connection that is preventing power from reaching the brakes. You can also check each brake's ground wire. All ground must be made to clean bare metal.
You can also refer to the linked article for more on testing brakes.
Tim
6/5/2024
Just to be clear we should apply positive +12v power to both the ground pin and the brake pin. No negative -12v ?
Product Page this Question was Asked From
CTEK MULTI US 7002 12-Volt Universal Battery Charger w/ Pulse Maintenance and Backup Power
- Battery Charger
- Battery Charger
- Car/Truck/SUV
- Motorcycle
- Trailer
- Lawn Mower
- Jet Ski
- 12V
- Charges and Maintains
- AGM
- Gel
- Lead Acid
- Shore Power to Vehicle Battery
- Smart Charge
- Trickle Charge
- CTEK Power Inc
more information >
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on Battery Charger
Bruce
7/30/2020
I tried to do this and when I touched the wires from the battery to the connector, one of them started to smoke. According to my new brake controller, there's a short somewhere. Could that cause the test wire to smoke?