Transit Mk8 Battery System.

[jimalikey]

Hi all, Please could I have some advice? I thought the dual battery in my Mk8 Tranny (2014) would be a Aux and Starter. But upon disconnecting one to find out which is which I noticed that either battery starts the van. Same works for all the electrics (lights/radio/fan) as long as one battery is connected all works. Somehow they seem to be wired in parallel, just wondering if a relay is broken that should isolate the batteries from each other until engine is on. Any thoughts???? Thanks Jim

 

[DandG5515]

My mk7 has 2 starter batteries wired in parallel under the drivers seat.

 

[sands-15]

Has anyone installed a leisure battery in 2020 mk8 under passenger seat..?

If so can you share parts used.. battery box etc..
Thanks