Gentlemen: I would like to reopen the subject of how to permanently disable the Eco Intelligent Stop Start rather than having to push the off button at every fresh start. I have a 2014 Jaguar XJ (x351) 3.0 Liter RWD and find that the stop-start feature is a safety compromising distracting nuisance.
I have read the posts suggesting disconnecting the negative terminal of the small battery but wonder what else will be affected by that action or by the eventual discharge of that battery. Has anyone tried using any of the other stop-start inhibiting circuits such as disconnecting the brake boost vacuum sensor or using the trailer connection to fool the system into sensing the car is towing?

 

Since there were no adverse effects when my small stop-start battery died, other than a stop-start fault message, I think you can safely disconnect the negative terminal.

I like that feature and had a new battery installed to restore the stop-start functionality.

 

Go to smartstopstart.com
Get in touch with Steve and see if he has any plans for the XJ?
You never know your luck!

 

Your lucky as Stuart says because removing the battery cable from the small second battery in the trunk will do the trick.

Later versions don't have the second battery and you must reprogram it off. On my XJR if in Dynamic mode it also turns off the start stop stuff.
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I disconnected the small battery on my 2014 and the feature has been disabled ever since. Good riddance.

 

1. Gentlemen, thank you for the feedback.
After disconnecting the small battery, have any of you received an adverse reaction from the Jag Dealership when taking it in for warranty service? Any consequence?

2. Steve, smartstopstart.com, advises that he is focused on GM models at this time since they do not have a disable button at all and owners are clamoring for a solution. He says he's is considering Jaguar in the future.

 

I haven't yet gone to the dealer yet but I suppose you could simply reconnect it beforehand.

 

Thanks, XJ8JR. Does the small battery disconnect leave an error code for the dealer to see?

 

I'm afraid I don't have the answer to that. Sorry.

Edit: I actually just ran a scan and U0447 came up, which signals a fault with the Start/Stop feature. So yes it does trigger a fault code, but not one that will actually give you a CEL or something.

 

Thanks for that quick scan, XJ8JR. What is "CEL" ? I'm new to the jargon.

 

CEL = Check Engine Light.

 

I would also love to see a permanent solution to this issue. I find it annoying in my Jaguar XJ and also my daily driver company car a 2016 Audi A3, the later I cannot do anything about though :-)

John

 

John, the correct technical solution is the one developed by Steve, smartstopstart.com. However, he has not developed the plug in Module for Jaguar yet. He says he is considering it for the future. I've been encouraging him via email. Check out his website.

 

Steve is Forum member WhiteXKR (The Jag Wrangler), whose Soft Top Remote Control is a very popular DIY accessory for XK/XKR convertible owners. It's what the factory forgot. Brilliant! See: https://www.jaguarforums.com/forum/x...o-video-109235

 

Thanks guys, I will check out the link and website.

John