I have a 2015 xf 3.0 supercharged. Just had is dealer for service and was told the small battery was weak. $500.00 for replacing. I have read you can unhook and it will disable start and stop at lights etc. I would be happy to have this stop but what other problem will this cause? Any help would be appreciated. Thanks kirk

 

Wrong forum ......... you want X250 forum. Just guessing the only problem this would cause is a message saying SS is inoperative/off?

 

Zero problems with disabling the SS system on the F-Type, heaps of us have done so, on both the earlier F-Type with the two battery system (2013 - 2015) or the later F-Type with the single battery (2016 - )
For the earlier F-Type just unbolt the end of the black cable which runs from the negative terminal of the secondary battery from where it bolts to the floor of the trunk/boot, or you can even remove the secondary battery altogether. I ran with the unbolted cable for a few years then about two years ago I removed the battery, zero problems in both cases and zero effect on anything else.
It should work the same in a 2015 XF.
If you want a new secondary battery it is an Exide EK151, hard to find but much much cheaper than a dealer supplied replacement.