Does Battery Need To Be Disconnected When Flat Towing A 2011 Ford Fiesta Automatic

Question:

What happens if I tow a 2011 Ford Fiesta automatic without disconnecting the battery?

asked by: Howard G

Expert Reply:

It is recommended to disconnect the battery on your 2011 Ford Fiesta automatic when it is being flat towed. Your vehicle has a feature that will not allow the battery to be discharged while it is being towed, so you should not have to go through the whole procedure you mentioned to reset the vehicles presets. To keep a maintenance charge on the battery I recommend using a harness such as # BX88206 with the tow bar wiring you will be using so that you can run a wire from the connector at the front of the truck to the vehicle battery.

There are a couple of ways to do this. First, you can tap into the running light circuit in the tow bar wiring but to provide power to the battery the RV running lights would have to be on all the time. Or if the connector at the back of the RV has a working 12 volt circuit you could use that circuit instead.

Which ever way you choose you would just attach the wire to the appropriate corresponding pin at the back of the connector that will be at the front of the truck and the other end of that wire will go to the positive battery terminal.

The Roadmaster battery disconnect, part # RM-765, receives a charge from the tow vehicle through the taillight wire on the 4-Way connector. When the motor homes lights are on, it activates the solenoid and allows 12 volts from the brown wire attached to the connector to maintain the battery.

I would not recommend leaving the battery connected when flat towing your automatic Fiesta since it could cause other problems. The manual transmission Fiesta does not recommend to disconnect the battery when flat towing so it might have to do with causing transmission problems. You might want to check with your local Ford dealer to see what the problems might be.

expert reply by: Jeff D