Parts Needed for Always-On 12V Circuit on 2018 Ford F-150 with Factory Wiring

Question:

DOES THE 7 PIN WIRING ON THE VEHICLE CHARGE THE BATTERY FOR THE BREAKAWAY SYSTEM ON THE TRAILER? WHEN I PLUG IN THE 7 PIN WIRING TO MY TRUCK, I DO NOT SEE ANY INDICATION THAT THE ELECTRIC BRAKE BATTERY IS CHARGING? ANY INFORMATION THAT YOU CAN PROVIDE. TRUCK IS A 2018 FORD F150 WITH FULL TRAILER TOWING PACKAGE AND FACTORY BRAKE CONTROLLER. THANKS

asked by: HUGH

Expert Reply:

The 12V auxiliary power circuit in your Ford's 7-way wiring setup is unusual. This circuit becomes active once you press the brake. It will otherwise appear to be dead. So unless you are driving there will not be power on that 7-way contact. This decision by Ford has caused a lot of confusion for Ford owners.

If you want your 7-way 12V circuit to be active at all times, regardless of the ignition key position or operation of the brake pedal, all you need to do is bypass the existing 12V circuit with a new direct battery connection. You will need just a few parts to accomplish this: circuit breaker # PK54540, 10-gauge wire # 10-1-1, ring terminals # DW05705-1, wire loom # 7509-10 and butt connector # 05732-2. These will let you make a direct connection to the battery + terminal and route the new power wire to the 7-way where it will connect to the 12V wire.

Once you have this always-on 12V circuit you'll be able to confirm that your breakaway battery is indeed receiving the necessary power to keep it charged.