XF 2009 - both key fobs not working

Mikeknight · June 5, 2020

Hi,

I've replaced the batteries and no joy. I can only lock/unlock manually via the passenger door which obviously is a pain. I need to put one of the fobs in the slot under the dash to start the car.

Questions:

How do I diagnose if this is a fob or car problem?
If fob, do I need to get a replacement? Can I buy from Jaguar or on the open market?
Is there a method to pair fob and car?
If car, can I fix it or does it have to go to Jaguar?

I have looked through a lot of posts and can't see anything relevant to my problem but if there is, can someone point me to it?

Thanks in advance for any help.

Mike

Jimbov8 · June 5, 2020

First thing Mike, check the batteries are in the correct way and the connections are not bent.

Reading the codes may show something as it is strange to have both fobs not working.

Big John · June 6, 2020

Hi

Did both Fobs die together? Did you change the fob batteries just before they stopped working?

If you did not change batteries and they were both working almost certainly not a problem in the remotes themselves. Can you lock / unlock with engine running? Almost certainly you need to get it on a diagnostic computer. Jag specialist is ideal if you don't want to face main dealer prices.

John

Mikeknight · June 6, 2020

Hi John,

The more used fob died first so I changed the battery which didn't make any difference. I then switched to the newer fob and all worked well. Over the last few months it's been harder to lock the car having to press very hard before anything happened although opening was fine. And then it died last week altogether despite changing the battery. For quite a while I've had to insert the fob into the dock as the car didn't recognise the fob was present otherwise.

There is no difference whether the car is running or not.

Think I'll have to find a specialist nearby to check this out.

Thanks, Mike

Big John · June 6, 2020

Hi

Do the doors lock / unlock ffrom the dashboard switch and / or the drivers door lock? To me it sounds like there may be a module problem (possibly the KVM) Hopefully it will be software and simply needs resetting.

Fingers crossed

John

Mikeknight · June 7, 2020

Hi John,

The interior switch works fine so I guess it might a module problem? Is this likely to be expensive?

Mike

Big John · June 7, 2020

Hi

Can't advise on cost as mine has a lifetime warranty so when my rear doors and windows stopped working after a flat battery I was not charged (if you pardon the pun). The garage I bought from is Fiat / Abarth / Volvo dealer but they have several Jag dealerships in the group so they simply rang them for advice. They told me it is a common fault and easily fixed by a software reset. As my garage is not Jag dealer I presume a standard "auto-diagnostic computer" can do the job. They kept it overnight to ensure battery fully charged but indicated it had been a simple and quick job. Apaarently the car stores several copies of the "as supllied" software files for each module so it is simply a procedure like doing a self test on ta home PC like scandisk and when it finds a problem it corrects the corupt file by replacing it will an original copy.

Hope that helps

John

Big John · June 7, 2020

Forgot to say. if it is simply that the remotes have died (I haven't heard that being an issue) it should show in the fault codes that are stored.

John

Catherine Walsh · September 23, 2020

I may have locked my keys in the boot (or the dog has them) but the other fob doesn't work to open the car. Any ideas??

Big John · September 24, 2020

Hi

No experience of the XK but presume there is an emergency key hidden in the fob as with the XF. You should be able to get in through the door (or boot) which has a manual lock.

Regards

John

Edited September 24, 2020 by Big John
spelling

Leo · September 24, 2020

John is right: The XK does indeed have an emergency key incorporated into the fob.

I used mine some years ago when I had a flat battery. The manual lock for the tailgate is behind the number plate.

Jimbov8 · September 24, 2020

If Catherine’s info is correct, it is a 98MY XK in which case it will be a key.😉

Mikeknight · September 24, 2020

Long story short, extensive diagnostics, car not talking to keys and vice versa, 2 new key fobs, £612!!

Bigvic · September 24, 2020

Sounds to me, and from your description, that you have two problems

You said that you had to press hard on the button to lock it and the unlock button was fine? This indicates that the actual button was failing, not the whole fob

Do the boot and headlight buttons work ok? Try both fobs

You also say that you have to put the fob in the slot for the car to see it. This is a totally separate problem.

there is a transponder in the fob, it could be the glass type or plastic, I don’t know, but this is not connected to the fob battery in any way. Some folk say it is, but it isn’t - trust me.

The car is sending a unique signal out all the time and this induces a tiny voltage in the transponder which, in turn, sends a signal which the car recognises, letting you start the car

it’s pretty unlikely that the transponders in both fobs have failed, so the problem, I think lies with the car’s receiver which is in the dash, close to the slot

in my humble opinion, I don’t thing shelling out a small fortune will fix all your problems, you can get the buttons on your fobs fixed, do a search for keyfob repairs, you can also get the switches from eBay for a few bob and do it yourself

This is the longest reply I’ve ever written!!