Why Does Battery of 2018 Ford Focus Have to Disconnect to Flat Tow It

Question:

The owners manual says to disconnect the negative battery terminal for towing. Is this only to prevent the battery from going dead I can run a charge line, or is there some danger that having power while towing on will cause transmission damage?

asked by: Bob R

Expert Reply:

In order to unlock the steering wheel of your 2018 Ford Focus the key needs to be in the on position. The problem with this is that it will drain the battery if left like that. So you have to disconnect the battery so that it doesn't drain and the steering wheel remains unlocked.

The Roadmaster Automatic Battery Disconnect # RM-766 that you referenced is a great solution for this as it automatically disconnects the battery and with the charge line kit part # RM-156-25 it can also put a maintenance charge on the vehicle as it's being towed.

I attached an install video for this kit on a similar 2018 Ford Focus.

expert reply by: Jameson C