My 2014 Jaguar XJ is giving me the message "Smart Key not Found, Refer to Handbook" - The battery had died yesterday so I had to jump it, once jumped it ran fine, but it would not recognize the Key Fob.

Both Key Fobs do not work - Also I tried changing the battery in one, and still no dice.

Does anyone have any idea? or Suggestion? Thanks a million in advanced.

 

When you say not working, does that mean the lock/unlock don't even toggle your door locks on the vehicle? Make double sure you replace with a new/fresh battery. I put a battery in mine and it turned out to not be fresh and the one Fob did not work, but once I replaced the battery, it was back to functioning.

Sometimes I get the key fob not found when it is in my pocket after I enter the vehicle. Taking out of my pocket and holding near under the steering wheel always picks it up. I believe the sensor is located under the steering wheel.

 

Thanks for the Reply. Yes it does not lock/unlock or do any function the the key fob should. I replaced the FOB battery with a fresh one and held it under the steering wheel. Its still did not pick up. The light cut on, and once unlocked the trunk opens as normal. But it look as if the Main car battery is defective - Hopefully that is the problem.

I am at the dealer changing the main car battery. Hopefully that will fix the issue.

 

Just to follow up incase it helps someone. The main car battery had a bad cell - So I replaced the battery and everything started working as normal....Happy days.

 

Glad to hear you figured it out. Every so often after i remote start my car, and i get in using keyless, i get the message that the key is not found. Which is obviously inaccurate, because it let me in the car. Sometimes i actually have to physically move the key from my bag in the back seat to the front, and then the car is happy again.

Just one of our "quirks and features" i guess, haha

 

Hi all< Just a quick message on this topic and hope it might help someone. Ive had my 2014 XJ about 4 years without a problem until last week when my Key fob stopped working with proximity. All of the other functions were fine, I could open doors and lock them pressing the buttons, I could open the boot. The problem was that the car would not sense the key fob when trying to start the car. I had to place the Fob against the dash bellow and right of the steering wheel.

I replaced the battery in the fob and no joy. I used the spare fob with new battery, no joy. I looked at many youtube videos and one over riding point made by people was to disconnect the battery, leave it for a while and reconnect. I did this, with the car unlocked, I removed the red positive and then the black negative. I even pressed the break pedal (Someone explained about draining capacitors - I just did it) I left the car for a little over 10 minutes, started to make dinner, and returned to reconnect the black then the red.

I got in the car, pressed the start button and bingo!!!!! What a relief. Jaguar quoted me £1000 for two new Fobs and the receiver!

One of the other messages I have had for some time is that the battery is low please start the car. That message has also gone. So in a nutshell, disconnect the battery positive and negative. Leave for 10+ mins. Reconnect and see if it fixes it, I hope it does. Good Luck

 

If you disconnect the battery you should short the + and the - cables together to drain any stray voltages.
Sometimes this works and sometimes it does not but since it's free you should at least give it a try.
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I just took my 2011 XJL to get a smog check and both my fobs stopped working. (One right in the parking lot of the smog check place!) Each have brand new batteries. After reading the above post, I disconnected the negative battery cable for about 1 minute and then re-attached it. Problem Solved! Thanks for this suggestion.

 

One comment?
When you disconnect the battery terminals completely from the battery it's a good idea to short the positive and negative leads together. This will drain any stray voltages.
Not a guaranteed fix but as you found out it's cheap and it might work!
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I feel really dumb but I had the same problem for a week, after changing the battery to my old and new FOB Key, the car would not turn on with the new key only the old one. I had to insert the old one in the key slot for my car to turn on. The New FOB key I have been using for almost a year, (yes the older one is way older 2009 Original one) would not turn on at all. I used new batteries 2032 and the packaging said expires February 2023, today’s date is 8/22/2024. This was NOT the problem.

After reading all the comments here I decided to go on YouTube check out how to change a FOB battery to see if there was something I missed. I was really convinced I was correct, but I checked anyway. LONG STORY Short. I have been suffering with an unlocked car for a week due to my uneducated way of installing a tiny little battery. Yes I know!!!!! I installed the battery the wrong way. I tried both keys FOBs separately away from each other and my car turns on and locks as normal. I was about to purchase a 150 dollar part. Good thing I decided to check out this forum and it got my brain gears thinking and activated my brain battery to double check my work. I feel so silly but I’m here hoping this may help others at one point or another.

NOTE: Check your battery installation before you do anything else. So embarrassing!!!

2032 FOB Batteries