Hello,

I’m trying to disconnect my battery from my 2013 Jaguar XF so I can work on my car and was a little confused when I opened the trunk and saw it… I checked the owners manual(which basically said take it to a professional) and even the technician manual too. The technician manual provides these instructions for the disconnect:

Pardon my ignorance, i’m not that good with cars and this battery is very different than what i’ve seen before. There were multiple things clamped on top of the terminal and the videos I used as reference(XE and Land Rover batteries) were far too different to use as a guide. I am just trying to disconnect the negative terminal so I can work on it but I am reading elsewhere (especially on this forum) about how not following a certain procedure can ruin some of the components and even fuse boxes? Read something crazy like having to open the trunk, wait, keep the fob away, and all doors closed?! Does anyone know where to find the proper procedure or should I just cough up the money and forget the DIY route(end goal is to replace three injectors which i’ve been studying for a couple weeks. Was feeling okay about it after hours of reading and watching, then got discouraged by the horror stories of people having to pay thousands because of commenting a battery!)

Thanks in advance.

 

There is a TSB about this but you don't really want to take this route as it will cost a fortune.
Taking it to a garage might not help you, as most people just expect to be able to disconnect a battery without causing problems, unless they have come across this issue in the past.
The procedure people have come up with is, to shut all the doors apart from the boot, take the keys well away from the car (as the keys will wake up the car) wait at least 30mins for full shut down & then you can disconnect the negative terminal.
You can recover the locking by usingjag SDD & running the immobilisation procedure, but of course disconnecting the battery again will lead to the same issue.

To be honest, I would not disconnect the battery unless I had no other choice.

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I also copied this from one of the FB groups.

​​​​​​The documented process for this, as first released in a JLR bulletin is -
Facelift X250 Battery Disconnection Procedure.
First ensure the battery tie down bolt is able to be undone by soaking with release/penetrating oil and test it. Then ensure the new battery is fully charged before fitting. Open the driver's door and leave open, open the boot and leave open. Leave the vehicle in this state and put the key indoors and leave it there - the key should be out of operating range of the car.
Leave the vehicle for a minimum of 33 minutes - critical time factor. Allow the car to fully shut down all its systems. When the car is completely shut down the boot light will extinguish.
Remove battery tie down.

Remove the negative clamp followed by the positive clamp.

Position new battery and fit tie down followed by the positive clamp and lastly the negative clamp.
The purpose of all this is to ensure that all the vehicle systems close down properly & fully so they don't lose active settings from corrupting live memory.
You will have to reset the one touch memory on all the windows.
An Ex Jaguar engineer commented on a previous post and gave this information which I have added -
“As a retired engineer from Jaguar, can I just add that whenever removing the negative battery lead from the main battery, it is advisable to re torque the fixing to the body on the other end of the negative battery lead to 14Nm & NO MORE. The negative lead when removed from the battery causes the fixing at the body end to rotate & it loses its clamping force & therefore becomes a partial connection”

 

I don't know what your local garages are like, but I'm afraid in my experience when it fails when they disconnect the battery, the dealers will just point you at the TSB and offer to sell you an new CJB + fitting!

So you may as well DIY if you have the skills for that. I imagine you will already have / be getting SDD anyway for the injector coding. So provided you have reasonable soldering skills to manage like in the pic in this post https://www.jaginfo.org/posts/2948063/ then I suggest it might be a good idea to order a BDM programmer ( xprog seems to be the usual one, I read 5.55 has problems reading dflash so better to get 5.84 ( or newer I guess ) ) in advance so you have it if you do run into serious BCM problems and need to fix them.

 

I done many jaguar Xfs, F-types for members on this Forum and I never take the battery cables off just use a maintainer , just remove the injectors and your good, here's a few videos to help

Go into my channel and there's alot of help there ,my next video I'll be showing everyone how to use SDD, and icarsoft v3

 

Listen to John Williams as he is an expert on this problem and has posted extensively about the repair procedure.
It's very common!
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For the life off me do not disconnect the battery, I've had to bail out many F-types and Xfsn from doing so ,if it's just doing Injectors put a maintainer on the battery, newer cars now are riddled with all kinds off modules, and each module needs to see a specific voltage to operate efficiently, all you need is a C-tec maintainer when you work on your vehicle ,when I did my cooling pipes and removed my supercharger I didn't use anything it fired right up like you see in many of my videos, but do as you think is right for you