XF stop start battery

[GAjon]

Can anyone please tell me if the stop start battery for a 2018 XF 25t petrol needs coding, or can I just take out and replace it?

Getting lots of different answers on line and also from suppliers.

If someone definitely knows it would be appreciated.

[t400ble]

Should be coded ideally
You can swap it then have it done

[GAjon]

Blimey that was quick, thank you.

I will probably opt for fitting and coding now rather than diy it.

Thanks again.

[liner33]

Jag often have decent deals on batteries

[8bit]

What even is there to "code" on a battery?!

[liner33]

8bit said:

What even is there to "code" on a battery?!

You code the car ie tell the car it has a new battery

[reddiesel]

8bit said:

What even is there to "code" on a battery?!

I thought this too , I just bang in another with absolutely no issue .

[Wheatsheaf]

reddiesel said:

8bit said:

What even is there to "code" on a battery?!

I thought this too , I just bang in another with absolutely no issue .

You're not "coding" in the new battery as such, you're telling the ECU that a new battery has been fitted. This is so the alternator output is set appropriately. If the ECU believes the battery is on its last legs as has been ascertained by recent sensor input (undervoltage, reluctant starting etc) it may charge a brand new battery inappropriately causing stress/failure. May not do any damage at all, but that's the reasoning.

[8bit]

Wheatsheaf said:

reddiesel said:

8bit said:

What even is there to "code" on a battery?!

I thought this too , I just bang in another with absolutely no issue .

You're not "coding" in the new battery as such, you're telling the ECU that a new battery has been fitted. This is so the alternator output is set appropriately. If the ECU believes the battery is on its last legs as has been ascertained by recent sensor input (undervoltage, reluctant starting etc) it may charge a brand new battery inappropriately causing stress/failure. May not do any damage at all, but that's the reasoning.

Ah OK thanks chaps - I have a 5.0 XKR and had to change the battery, did the BMS reset procedure with my iCarSoft diagnostic device - just never heard of it called "coding" the battery so wondered if this was some new thing to try and keep people using main dealers. BMW and Mercedes love coding things for a nice price.

[NortonES2]

Didn't think the X260 had 2 batteries.

[GAjon]

To conclude this story and possibly be of help to anyone who might need to change the battery on a 2018 XF 25t. ( it might be the same for all post 2017 XF, but I do not know that for sure).

It’s probably more accurate to say a new battery requires registering rather than coding.

As correctly stated above it is recommended the XF battery is registered when newly fitted, so I decided to get one supply and fitted.

I purchased one one line and booked it in for fitting at a local Halfords, unfortunately this went completely wrong for many reasons culminating in the fitter saying he didn’t have the correct tool to do the job so I got a full refund.

This lead me to start phoning around getting different advice from each garage.
Yes they do need it, no they don’t need it, we wouldn’t take it on etc etc, A Jaguar specialist quoted 1 hour to fit and 20 minutes to register- £160 plus the cost of a new battery, no chance.

So after a lengthy in depth study of several minutes decided to do it myself.

My main resource that brought me to that decision was a site of a battery manufacturer and also a manufacturer of the tools that are required to register new batteries.
The up shot is it’s recommended to do, but not critical.
It essentially records a memory point off the car’s computer then restores that save point when the new unit is fitted aswell as telling the cars computer the battery is new.
If you don’t do it you may loose some functions that you can reset individually manually.
After a few trips or miles the car will recognise the new battery anyway.
There is no danger of over charging the new battery or it damaging the ECU.

One thing is recommended is you get an exact same spec battery, which is what I did, slightly more expensive than the Halfords one, but an exact match both physically and technically.

So, what happened?
I changed to battery 20 minutes including a brew.
The tail gate ( it’s a sportbrake) wouldn’t close on the button, so manually close it, it remembers where it is then works fine.
The global window open worked for down but only the fronts went back up.
So, just run both windows through a full up/down try again all ok.

Everything else worked as it should, it didn’t even loose radio presets and the stop/start worked immediately.

I don’t know for certain if this would be applicable to all XFs but it might be of assistance to someone.

[TarquinMX5]

Thanks for updating, very useful. Regrettably few people seem to update threads nowadays which means others can't benefit.

As an aside, I've heard similar stories with MB, where the recommendation is to update the car, ie for filter change but it would seem that the car relearns the new parameters fairly quickly, much as it 'learnt' whilst the original item was gradually degrading.