I recently bought a 2011 Jaguar XF. I soon realised that the eco stop start was not working. After a long drive I noticed it would work for a couple of days and then stop working again.

After reading a few threads on here I decided to buy a new auxilary batter online and fit it myself hoping that it would solve the problem. Unfortunately, after fitting the new battery it did not work, however, after a long drive it started to work for a couple of days and then stopped working, exactly the same as the old battery. If anyone could help me understand what is going on or how I can resolve the problem it would be hugely appreciated.

TIA

 

Wrong forum.... you want X250

 

Yes wrong forum but I think the system is working properly?
Many things impact whether the car will shut off at stops or not. So it's not consistent even when working OK.
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