Folks, a couple days ago when starting my wifes XF, the car cranked weakly as if battery was dead, but I attributed it to me prematurely lifting my foot off the brake while pushing the start button, because I immediately retried the start with more attention paid to the brake pedal and it cranked fine and started.

Today, 2 days later, my wife arrives home from work in the car with no reported issues. I got in it to go to the gas station and very weak crank and no start. I determine it must be the battery, so I pulled the known good battery out of the s type in my garage and swapped it into the XF. Still nothing, even though I know the battery is good...but NOW IM GETTING MESSAGE SMART KEY NOT FOUND. So...reading the manual I decide to dock the smart key fob into the docking port but it refuses to accept the smart key with message "CHECK SMART KEY"...... I then replace the battery in the smart keyfob to make sure it is not a dead battery there. No difference. The radio comes on, interior lights are on but the headlights will not light up on demand, and the smart keyfob is apparently doing nothing..it wont lock or unlock car, or turn on the lights. Now I'm panicking

We just bought this used car a few months ago and only received one smart keyfob that has been working fine until this episode.

What has happened? I read on another thread that if the smart key docking port refuses to accept the smart key with message "check smart key" it indicates the keyfob is not for that car...but how have i been driving it for the past 3 months if that was the case?

Help please.......

 

Can you get the ignition to come on (ie press start button with key inside the car and without your foot on brake)?

Check smartkey battery - occasionally new button cells are dead on arrival. Also did you definitely fit the right size - CR2032? And is it the right way up?? I've made that mistake before...

Also bend the contacts on the circuit board and the edge battery contact to ensure they are connecting to the battery ok

 

thanks for response , britcar. I used a 2032 battery and made sure it is right side up. I also bent out the connector tangs. I guess it is possible the battery is defective. I tested the car battery with meter and get 12.47 v. No, i can not get any ignition attempt at all from the car. The start button does not illuminate at all, as it did before. message keeps saying "smart key not found" and when docked it says "check smart key". a local Indy jag mechanic told me that sometimes when car battery is disconnected and replaced, the smart key communication is lost and a procedure he called performing a "handshake" remedies the problem. he said that is not the same as reprogramming the fob which only a dealer can do, and if I get the car towed to him, he might be able to save me a dealer visit for $135. I'm going to gamble that $135, because I would rather avoid a dealer visit if possible. any further thoughts on this are appreciated.

 

Be sure and get a 2nd key too!
Just too dangerous to only rely on one key.
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Try disconnecting the battery and letting the car sit for an hour. Once the battery is disconnected step on the brake a couple times to dissipate any residual power.

 

Thanks for input......I just had the car towed to a local Jaguar indy. So far, everyone has been very gracious to me...tow truck driver waived mileage overage from AAA coverage, indy shop told me if he can't fix it he will not charge me a penney for trying. I hope he is able to obviously but not holding my breath.

I am still puzzled why the keyfob is not communicating with the car whatsoever after I disconnected the battery to put a different one in. Never had that happen on any other car I've owned. And the deeper I get into this XF, I become more trepidacious over the future with it. With this keyfob not functioning, literally nothing can happen on the car....not even roll down windows. Seems like some overkill on the electrical "conveniences" with this model. But I own it so got to deal with it.

 

Good luck. Report back what you learn

Sadly sounds like fob may have got damaged during battery replacement as even if the passive system isn't working it should still work when docked

 

so got the car towed back from indy shop. He wasnt able to do anything with it. The car battery is questionable because it will ot hold a charge at all. When I too it to the ship it was at 12.3 v and when returned home, everything was completely dead with battery only reading 6 v. Took it to autozone to test and verify it was bad, then purchased an expensive H8 AGM battery. Praying for the best as I installed it but no joy. So, all the interior lights work, radio works, but here is what is not working....can't set park brake, steering wheel does n ot lock up in park with no engine, and doors wont lock or unlock nor windows do anything. the start button illuminates with smart key in car and doors closed but no engine cranking. messages are smart key not found and when docked it says check smart key. I am racking my brain to see what I could have done to destroy the keyfob. All I did was disconnect and replace the car battery with one from another car, and I replaced the 2032 in the keyfob. What did I do? Looks like I;m headed to the dealer

 

Wonder if the sensor ring in the dash is bad and can't see the fob anymore?
That should set a code so maybe the dealer will find the problem.
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As clubairth said checking the codes will hopefully show the issue.

Regarding changing the battery, with the XF you only need to program the new battery for the BMS (battery monitoring system), doesn't affect other functionality. I've had the battery of mine many times and many service tasks require doing this anyway.

Your description matches what my car does if I leave the key out - basically only the radio and lights work. If you don't have a diagnostic device yourself I think it's best to go to the dealer to have it sorted out.

 

Dare....thanks for the feedback...can you elaborate a bit? "program new battery for the BMS? do i need to do this and how? For you and everyone here, I am pleadiing for help...and I am today freaking out. I called the Jag dealer to prepare myself for the upcoming visit scheduled for next week and service manager there said best case scenario is I'm lookiing at $500 for key re-programming/initializing or whatever, but worse case scenario is if a module and/or ecu is damaged I might be looking at $2000!
I'm about to be a grown man crying hysterically. I can not afford that at all.
In speaking with my son about it who is somewhat of an ebay wheeler dealer aficianado, he says just get written estimate from dealer if it is beyond key reprogramming, and he will guide me thru buying used module or ecu for fraction of dealer cost and then figure out how to get it programmed?

People.....can you somehow calm me down? Dare....I plugged in my ELM to the obd port, but without ability to get car into "ignition 1 position, how do I get it to communicate with my Torque app? All it does is say unable to communicate with ecu. So I experimented by plugging ELM into my little chevy car with no ignition key, and same thing. It will not fiind my Torque OBD tool. I appreciate your assistance. I'm in trouble here

 

Aftermarket OBD scanners can't access all the features a JLR diagnostics device can do. I can't say for sure if you'll be able to read the car with the JLR device if it won't turn accesory power on and can't check with mine right now as I don't have it handy but I'm sure a dealer can get it working, no problem at all. With an issue like this, you most likely need the JLR approved equipment to get it sorted.

BMS programming you shouldn't worry about right now. It resets the BMS telling it you have a new battery and it will treat it as such. It's purpose is to monitor the condition of the battery and warn you if it sees upcoming issues, which it determines by how the battery acts, as far as I know. What you could do is that when you take your car to the dealers tell them you replaced the battery but haven't had the BMS done so they know to do that as well. This is something any decent battery replacement shop could do as well, and they charge usually some 50 $ for it where I live.

Regarding the ECU and reprogramming:

Generally speaking you need at least some 500-600 $ worth of equipment to do programming to your vehicle safely. It also takes some knowledge on how to operate them, and unfortunately my knowledge is limited to simple self-servicing of my car, not reprogramming of the ECU. You'd want some expert input on that. Whatever you do, do not buy cheap 100 $ "genuine" JLR diagnostics tools and try with them. They are cheap chinese copies and could damage your car in horrible ways. Usually it's best to let experienced shops handle stuff like this.

My advice is now to relax and not paint demons on the walls. You don't know anything for sure right now, and it could well be a simple fix. As your son said, let the dealer check it first and see what they find.

 

Thanks for continued help on this issue. UPDATE........I found a local locksmith who advertises ability to program all European cars, including Jags and decided to take a chance on him since he said he was confident he could get the job done or no charge me. Result......failure. He tested my remote (smart keyfob) and found it to be transmitting a signal, so more or less ruled out defective key, but his computer could not complete the testing cycle as desired. He said it is something else and time for the dealer visit.
He did ask me about why the steering wheel was not locked with no ignition, and reported that in the past, the failure of steering wheel to lock on other cars he has worked on was part of the problem with key not programming. I started thinking about it and now wondering if this thing called a KVM (I believe referred to as immobilizer) and the device that talks to the remote, also sends signal to steering wheel lock soleniod, and if that is bad, it could be the root of my problem????

The dealer has prepped me over the phone for possible KVM or ECU and an expected worst case of $2000. I am now resigned to a very expensive dealer visit on Thursday, If anyone has further thoughts on this KVM possibility I would appreciate hearing.
To be honest, we don't remember if the steering wheel has ever locked since we purchased this used car only about 3 months ago. I'm painting those demons.

 

I don't think your steering wheel locks? I have a 2014 XJR and it does not lock the steering wheel at all.


You have done good troubleshooting and have verified that the key/FOB looks to be operating correctly. I think the problem is in the car at this point and you need to go to a dealer. I also think his term KVM is the receiver in the car that interfaces with the smart key. This is usually a ring or small module (Keyless module?).


Be sure and report back what codes you get because this is all a guess until we can get some real information about the system status!
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update...car has been at dealer for 2 days and they finally called me to tell me "bad news"........basically they don't know what happened but they need to order 2 new keys and a kvm (module) and a "fuse box" that is somehow connected to the KVM. There is zero communication to the KVM and so they are deeming that module fried and can't just order one key because.....in order to program it, they need 2 keys. This is simply what I am being told by a Jaguar dealer service center. I am at their mercy at this point since the car can't be started at all. I COULD shop online and attempt to purchase the parts they are now ordering from Jaguar, but even then they would have to program the apparatus. If I paid a tow truck to haul it home, I would still have to tow it back for programming. Expensive 40 mile tows.
They can't explain how this all happened by me simply disconnecting the car battery and hooking up another one, saying it is highly unusual. That is not comforting actually. They are going to charge me for the parts and labor....$2045 !!!!!!! for an almost 10 year old car. I'm not happy, but welcome any feedback or ideas from you guys.

 

No advice as it's a real rare problem and I can't say I have heard of it before. At least not the part where every last piece of the system needs to be replaced!

Keys can be married to modules all the time and replacement keys are common but without any codes or further description we will just have to accept the dealers explanation?
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yes, I am at the mercy of dealer on this. I have seen other threads with people reporting blowing the KVM with a battery change, and theories that a hot battery (fully charged) can cause a spike when connected, noting visible large sparks upon connection. I will admit that when I connected the new battery to the car, there was a pretty good spark at the terminal. That is when all communication was lost. Other comments on those threads even mention blowing the KVM with a battery charger connected. This really is a disturbing situation since I just bought this nice car about 3 months ago for my wife and had hoped it would get us into the sunset without a lot of headaches. We are retired persons on limited fixed income, and large expenditures on car repairs are not budgeted. Hoping for the best.

 

Wow, I’ve pulled the terminals off my battery many times for various reasons and got that spark every single time the last terminal is connected. Fortunately I’ve never had an issue restarting after...
Did you try connecting a lead from the negative to positive wires with the battery disconnected in order to totally discharge and reset the system?

 

I have too but we do have these once in a while failures like this.
Still not sure why?
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No I did not do that. That's about the only thing I didnt try. So, in effort to avoid a dealer visit, I had the car towed to an indy mechanic who claimed he could program jag keys...he couldnt get any communication out of it. Had a locksmith who claimed he routinely programs jags come out...he couldnt get any communication out of it. Towed to dealer, they dont know what caused issue, and he disputes others on internet that a simple battery disconnect and reconnect can cause total communication loss, but in any event, he says I need new KVM, keys to go with it, and this thing he called a fuse box but is not a fuse box.
It's so unfortunate that dealerships have earned the reputation and mistrust of most of the public due to overcharging and taking advantage of people. In actuality, the new car dealer SHOULD be the guys we trust the most. I know no matter what happens I will be paying top dollar to get my car back whether I can afford it or not.