Do I Need a Battery Disconnect for a 2021 Ford Edge?
Updated 04/09/2025 | Published 04/03/2025
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Question:
I bought the BX2677 from e-trailer and have installed the baseplate. Im almost done with making the openings in the facia that had to be removed to install the baseplate. My question actually involves the procedure to put the 2021 Edge in flat tow mode. The Ford owners manual describes how to disconnect the Park lock function by pulling and latching the cable found under the dash. The Ford owners manual also suggests disconnecting the negative battery cable to prevent the parking brake from coming back on if it senses motion. I tried this with the Edge long before I even bought the baseplate and I could roll it forward and back by hand without disconnecting the negative battery cable. Now that Im almost done, I can disengage the Park lock, but as soon as I roll the Edge a little bit and stop, the parking brake engages. Surely, Ford does not really expect owners to remove the air filter, the air filter housing and the battery to get to the negative battery cable every time they want to recreationally tow the Edge ST. Have you had other customers with the Edge ST encounter this difficulty? I could get a battery disconnect switch, but the Ford Edge had multiple wires connected to the negative battery terminal assembly.
asked by: Cullen D
Helpful Expert Reply:
We have run into this issue before actually and spoken to Roadmaster about it. The only solution that doesn't require the extreme amount of difficulty you have described is to install the Roadmaster Battery Disconnect for Towed Vehicle w/ Flat Tow Brake System item # RM-766. This part isn't listed as optional as far as flat towing your vehicle goes on Roadmaster's website. It's listed as one of the required parts.
I have linked a couple of installation videos we've done on the previous generation of Ford Edge's below. We do not have one on a 2021 though.
If you have any additional questions feel free to throw them into the comment box below.
Product Page this Question was Asked From
Blue Ox Base Plate Kit - Removable Arms
- Tow Bar Base Plate
- Removable Draw Bars
- Twist Lock Attachment
- Completely Hidden
- Blue Ox
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Cullen
4/6/2025
Thanks for the timely answer Jerred. I was thinking of using a battery disconnect switch on the positive terminal side even though the Ford owner's manual procedure specifies disconnecting the negative battery cable. Even that instruction is confusing because there is a large bracket mounted to the negative terminal - the main battery negative cable connects through a lug, but there is still some sort of small electrical module connected unless the owner disconnects that whole large bracket. I did see that RM lists a battery disconnect switch as needed, but I did not buy any RM components, so I never explored why that was listed. I will buy the RM-766 when I'm done with the rest of the installation - it seems to be a better quality than some of the manual switches and it will be more convenient than having to go under the hood to turn off a switch. Kudos to e-trailer from your consistent great help and wealth of knowledge.