Hi, I recently purchased a 2016 XF 3.0 from a auction and the car drove home and everything was fin. I parked the car and when I returned to it I had no electric power other than the doors would lock and unlock and the Jaguar emblem would come on the screen. I charged both batteries. Still nothing. I read on here that not applying enough brake pressure would cause it not to start, tried that and nothing. I tried the locking and unlocking before entering the car and that did nothing. The car then sat for a week and a buddy of mine went to look at it and it started just fine. We took it for a drive and everything was good. A week later its wouldn't start and hasn't started since. Any direction would be greatly appreciated. Thank you in advance.

 

Any idea why it was auctioned off?
Might be a clue?
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Bring your buddy back and see if he can start it again. Watch what he's doing and talk to the guy while he's doing it.

In my no-start case I was simply not pushing the brake pedal hard enough. See my handle. My 2017 Subaru just needs a touch on the pedal to start, and that was my frame of reference. But I found the Jag requires a manly shove.

Get a trickle charger on there to preserve the battery until you can get busy on it.