Hi everyone!

It's my first days driving my new Jaguar XF 3.0 2008. Today while driving slowly at traffic jam car totally shut off. All electrics, engine, everything. No buttons even that one with red triangle didn't worked. After few minutes it started with no problems but all of settings incl, trip computer, time etc. looked like it was full reset to default.

What do you think it could be?

 

Earth grounding issue most likely. Check the visible parts of wiring harness particularly around the battery terminals, grounding connections from the battery etc.

also check battery voltage to see if it's failing

Could also be a break somewhere in a main wiring harness but I'd definitely start with main connections and grounding leads

 

Start/stop battery dead probably. System shut down and couldn't turn back on.

 

Not on a 2008 model

 

Battery terminals loose?

 

I had this exact same issue with my xfr 2010, i turned off mine then on, started right away and it was like nothing ever happened, my counters got reset too.

After some research and searching in forums i found out that a permanently connected OBD 2 dongle has been reported to cause this, i had a Elm327 dongle in the slot while this happened.