Hi everyone, I know there are multiple threads about battery draining on Jaguars, and there might be multiple different reasons for the issue..

But I've finally solved the issue on mine, and thought I'd share it here and hopefully help someone out.

I've owned my 2011 XF 5.0 V8 for over three years now and I had the electrical issue from day one. Did ton of service on the car including a new generator and battery but nothing seemed to fix the issue. Ended buying one of those portable battery starters to not risk getting stuck somewhere. The car rarely managed to sit for more than a week without getting start-up issues, I could easily distinguish when the battery started to have a low charge on start-ups..

But now... the car has been sitting for multiple weeks, multiple times without showing any signs of a low battery charge and all because I fixed another issue on the car which seems to have sorted out the battery drain as well, lucky me! 😇

So here's what happened.. my infotainmentsystem started lagging on start-up, the computer kept rebooting for several minutes before finally booting up like normal, and this happened everytime I started the car.. why I had to find a fix for it.

The FIX:
I removed the driver's seat, fairly simple process, there's multiple videos online. And then I removed the Bluetooth-module and the Satcom-module, they are plugged in one after the other via a fiber optical cable, so I just had to remove those two modules out of the loop. No extra equipment needed. This fixed the infotainment system, no longer lagging on start-up and surprisingly doesn't seem to drain the car battery anymore!

Hope this can help! Best regards Leo.




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Good find!

 

So, did you replace them?

 

Any sign of water damage on the pins?

 

[QUOTE=kkurulak;2817911] I did not replace the units, the bluetooth was already not working when I bought the car. I bought the car in the US and brought it back home so didn't have any use for the satcom unit either.

There were small amounts of corrosion on the satcom-module that sits closest to to the floor. Can't recall how the pins looked.

 

[QUOTE=Leo_77;2818070]I'm sure if this will help but I have a 2015 XF 3.0 supercharged AWD. I learned very early on that in order to complete the shut down process you must lock the car after shutting down all of the inernal systems including the various screen savers. Then you must lock the car and set the alarm system using the locking rubber tabs on each door with the car keys a safe distance away from the car.

If you dont there can be a parasitive drain on the battery as the car is constantly looking for the key in case the owner suddenly appears with the key in anticipation of opening the doors. Its sort like leaving your dog home alone while you're away at work. The dog is constantly pacing around the front door awaiting your return as if to be ready to ponce on you at the exact moment you return. In other words using this analogy the car is waiting as if to say are you home yet?

This small drain on the battery isnt much but ovet time it can easily drain a full charged battery. As I drive my car only occasionally I found this out the hard way.

Now I connect my battery to the quick connect/disconnect leads on a battery tender and have never had a problem. As most modern Jaguars utilize an AGM battery this is especially critical as AGM batterys seem to prefer to be on a constant state of charge.

My wifes car is an Audi Q5 SUV that again sits for long periods of time. We used to go thru batteries at a much faster pace until we used the same process on her vehicle. I can only guess that AGM batteries which her Audi also has just dont like sitting around with less than a full charge.

Since we have used the battery tender maintainers/chargers the batteries have lasted much longer plus a set of battery tenders is much cheaper than two new AGM batterys.

In addition as I do most of the vehicle maintenance myself, not having to dig around in the trunk area is really a plus. Getting to the battery in the Jag or her Audi takes a fair amount of time as you must remove spare tires as well of a number of internal storage boxes before you can actually access the battery it self.

The only problem with this approach is that you must remember to disconnect the battery tender leads. I've solved this issue by using a bright yellow extension cord lead which has a built in circuit breaker with 6 plug outlets placed between our two vehicles. The bright color seems to alert both of us to the fact that the battery(s) are connected to the charger(s).