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2014 Jaguar XJ - Idle Stop Battery Info

Ray, You did an article on the feature of an engine stopping when the car is at rest. In Naples, FL we turn it off because the A/C won’t run when the engine is off. Way too hot to use that feature. I have a Jaguar and after asking them to permanently disable it (and told it couldn’t be done) it quite. I thought they did it and recently had service where they wrote in their report that I needed a $350 battery. The main battery was fine. Checking on the internet it seems this second battery’s only function is to restart the car when the ECO is on.

This doesn’t seem to hurt the car’s operation and I have to wonder how many shut offs I would need to save $350 in gas.

Maybe keeping the old dysfunctional second battery installed is the easy solution for your Jag. You can use the forum search feature for more info if you want; this automatic start/stop function is a pretty frequent topic here. Click search icon, upper right, this page.

I’m guessing the reason that it can’t be turned off all the time – in normal situations – is b/c it is part of the emissions system; i.e. the car’s mpg & emissions system ratings are in part a function of auto start/stop working.

I’m not Ray btw, just one of the diy’er posters here.