Auto On off

[dglick]

HI all

Ive got a 2016 Xf sport, with 21k on the clock. The only thing not working is the auto on/off.

 

Ive booked the car in for a service at Williams, but they have said the usual problems with the auto on-off require the car overnight, which seems a bit bizarre to me, anyone else had same experineces, or can offer any advice ?

 

Surely it can only have a button (Switch on and off seems to work), a sensor, and sufficient power in battery ? Even if its the battery cant these be tested / topped up ?

 

[Trooper2142]

Welcome to the Jaguar owner's club.

The garage will probably charge your Battery over night to check if that's what's wrong with the Battery, that's what the Ford Garage did with mine because the Stop/Start didn't work.Charging over night didn't work so they fitted a New Battery which is Higher Rated and everything is working as it should.

Regards Tom.

[Big John]

At 4 years, could need a new battery and it must be an AGM not an ordinary one so probably looking at thick end of £300 at a Jag main dealer (around £180 fitted at Halfords and the like).

If you are not doing many long journeys it could simply be in need of a charge. If you park on your drive I would get a Ctek maintainer (£70ish) to keep the battery topped off. I also use the Ctek Battery Sense which is a bluetooth device (£50ish) which connects to your mobile phone and monitors battery state so that you can easily see when you need to "top-up" the charge.

Modern Jags (and all premium cars) are essentially a bunch of computers on wheels and take a surprising amount of energy even when seemingly dormant. If you get one of those cigarette lighter voltage displays and sit in the car with the engine off you will see a frighteming rate of discharge!. The last thing you want to do is let the voltage drop enouugh to start corrupting the computers software which can be fiddly to repair. It is why they have the second, smaller battery. When the Stop/Start stops the engine this takes over as steady power supply for the "sensitive" components leaving the main battery to sort out restarting and basic "in-sensitive" functions such as the air-con and lighting.

Regards John