Hi all

Hope someone can help with a problem that started yesterday, when of course we are on holiday and nowhere near a jag dealership.

Car is a 2011 XJL. I am getting the ‘smart key not found’ message when trying to start. Changed the battery in the key fob and after a few fails it’s started and got me back to holiday home. Started first thing this morning and then about 100m into drive the message again appeared which I found strange. Parked up for a few hours and it started no problem when I got back so thought it was sorted. Went to a local garage to see if they could test the main car battery but of course when I tried to start it again had repeated fails for about an hour before it randomly started.

so
1. have changed the fob battery. A few times.
2. I have followed the manual instruction and placed the fob below boot open button but this hasn’t proved effective
3. Main battery test result was good but needs recharge. normal driving is local and low speed but the last week has been long distance at decent speeds so battery should have been charged up.

I am now cutting my holiday short as I don’t want to get stranded in the middle of nowhere and drive it home to a jag dealer to get them to check.

I have read other posts but these mainly were solved by changing fob battery and placing it close to dash. As mentioned this hasn’t worked.

hoping someone here might have some suggestions.

any help appreciated.

thanks

 

When I change the smart key FOB battery I almost always have the error until I have cycled the car off and on as well as using the FOB to lock and unlock the car several times. Seems like there is some kind of initialization going on and after a day or so it all works. Is yours still messed up?
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Your XJ is a 2011, so the fob battery has been replaced many times over the last 10 years. As a result, it's likely that the prongs that hold the CR2032 battery in place have been stretched a bit and caused the battery to make intermittent contact. Don't try to bend the prongs. They're easily broken, can't be repaired, and you'll have to buy an expensive new Smartkey.

Here's the easy fix. Make a shim out of a small piece of aluminum foil and insert it under the battery so it's snug.

Note that CR2032 batteries sold on the internet may be counterfeit or old stock duds. I buy my CR2032 batteries locally from a national chain retailer where I know they're genuine and I can check the date so I know it's fresh. Buy a 2-pack so you can keep a spare CR2032 in your glove box and have one when you need it.

 

If I keep my Smartkey fob in the same pocket with my Smartphone, I'll occasionally get the "Smartkey not found" message.

 

Good info Stuart! I have been buying new replacement FOB's off EBay when mine start acting up. They are cheap enough that it's not a problem.
Hope the OP comes back and lets us know what happened? He made one post and then disappeared.
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