So, a new one on me in my few months of F-Type ownership: I've occasionally seen the "low battery - please restart" message after the car has sat for several days; I tried the battery disconnect/reconnect, but the only thing that seemed to get rid of the message was a long (>30 minute) drive. So far, so good, no big issues.

Saturday, I got back from a 4-day trip, got in the car at the airport with no messages. Drove home, locked the car; again, no "low battery" message. The next morning (yesterday), I got in the car and was met with a "key fob not detected" message. I tried holding the fob under the dash; still no luck. I got the second fob, but was met with the same result.

I again disconnected the battery and reconnected after about 30 seconds; all is now normal again. My guess is that the car never fully went to "sleep" on Sat. night, because it was detecting the fobs sitting in a drawer in the house about 12 feet away. So, anyone else ever see anything similar?

 

They (we?) do recommend not keeping the fobs near the car, for precisely this reason. Never experienced it myself, but the fobs are never stored near the car.

 

I'd have thought the detection range would be considerably less than 12 feet, nearer 3?

 

I would have thought the same, but have noticed on more than one occasion that the car won't completely shut down with the car in the garage, and the keys nearby inside the house. Until this latest occurrence, the symptom of this non-shutdown was that the little hazard marker triangle on the center stack would not go out, even after significant time. If I moved the key fobs out of range, the triangle would go out almost immediately. This weekend's issue was a bit different; the hazard triangle did go out, but the little LED's next to the power door lock buttons stayed lit. This time, instead of just displaying the "low battery" message, the car wouldn't recognize either fob, even placing them in the spot under the dash. This left the car dead until I did the battery disconnect/reconnect.

 

So I took my car for regular service at my local dealership. I also had a check engine light related to a small canister leak and failed O-rings on the air conditioner. The car came back with the dreaded battery low warning.
My first issue is the dealership simply handed over the car and ignored the warning message. Putting that aside, once I called it to their attention they adamantly refused to acknowledge it was a problem at all.

I am well aware of the long history of our cars’ battery problems and the standard solution of doing a hard reset by disconnecting the battery when an OBD reader connection has stalled out the sleep mode. My service advisor refused to acknowledge either the problem or the solution. She insisted the car won’t go to sleep in less than 40 minutes and all would be well after. So....we watched and waited but the car never went to sleep. She continued to insist there was no problem. All I needed to do was drive the car around for a while and it would be fine. I continued to insist that the sleep mode would not engage and that the battery would drain. Finally, I gave up and took the car home.I drove around for two hours to give her solution the benefit of the doubt. As expected it drained overnight as sleep mode never engaged.
Following advice on the forum I did a hard reset and all has been well since in terms of the sleep mode engaging and slow discharge of battery ending.

I tried to talk this out with my service advisor but she continues to insist that basically I don’t know what I’m talking about and any advice I find on the forums is not valid as it’s just a bunch of enthusiasts who don’t really have the bigger picture. Sort of a proverbial pat on the head to a little kid and his funny friends.

Needless to say I’m pretty ticked off about the whole situation; but putting aside my hurt feelings I’m asking this group if my advisor has a point? Is she right or is the battery discharge after plugging in an OBD reader real? My advisor insists she has never seen any battery issues except for one Land Rover. I find that hard to accept.
I’ve decided to escalate to higher levels of management at the dealership. My ask is going to be a new battery given the damage that occurs when the battery is run low. I’d be interested in what your thoughts are?

 

The OBD issue is not widely known among the dealers. Even the best intentioned of the bunch will deny its existence. We even have a Jag tech on the forum who adamantly opposes the existence until I spoke with him by phone to present evidence of correlation between OBD access and the sleep mode failure. He has since bought in to the issue/resolution and has even offered up some theories for why it occurs.

 

Well, she hadn't seen yours! If she refuses to believe there's a problem she won't see any. Hopeless.

 

Felt like I should through my $0.02 in on this again (just got done saying the same thing on a similar thread here a couple of weeks ago).
I purchased my car in July '18 CPO with 17K miles on it and I have all the paperwork on it. It had been leased in southern California where the dealership there (that will remain unnamed) replaced the battery in the car 5 times during the lease due to this same issue and the battery going dead and the lease holder finally turned the car back over to JLR under the California lemon law. This says to me that at least that dealership had no knowledge of how to correct this problem.

I subsequently have put 13K miles on the car and had zero problems until three weeks ago when I experienced the "low battery, restart engine" and the red triangle hazard light being on for days ahead of it. Having read the discussions on this forum I did the battery disconnect, hard reboot. Worked like a charm, no problems since. The only thing I will add is that I let my situation go too long and the battery was drained too much to the point where the battery was acting flaky and not accepting the charge from the battery manager. Once I did the battery reboot, that allowed the battery manager to perform a nice steady charge of the battery.

It seems that JLR's reaction and understanding of this issue is very puzzling.

 

Is it allowed to make a slight sidestep ? I am aware of the use of the OBD2 socket and possible faults resulting. I have been trying to get a type of OBD2 'allowed' by JLR as I need
to use one to make roadmovies with speedo /rev/turbo metered in the same screen. They don't reply since jun 2018 and I recently started to light a fire under it again.

Is it always a problem if you put any OBD2 plug in, or is any brand or use problemfree ? If I only use it to link data by bleutooth or wifi to my mobile : wiil sleepmode be hampered too ?

I have many years of guarantee left and don't want to hand them any kind of a stick..

 

I don't believe anyone has figured it out completely. It seems that only some cars are affected by the issue, and then only by certain plug-in equipment. Even then, the process for disconnecting can impact whether the problem occurs. In no event can I imagine that it will affect your warranty, as all info is flowing from the ECU to the device, and you aren't modifying any files on the ECU.

 

I thought so either, but then a friend told me about the different configurations in special brand related OBD2 pins, and it might cause a shortwire in a circuit.
Therefore I also queationed a major garage equipment dealership in the Netherlands if they were aware of this, or if they had a brand of OBD2 plug that
covered a possible shortwire with an insurance. The never even answered.

 

I continued to work this issue and carried it all the way to Mahwah NJ headquarters. I eventually received a somewhat oracular pronouncement from the engineering seers:

• Yes, we have heard of the battery discharge issue.
• We think it is a real issue
• We think it is a very rare issue
• The discharge should not occur when connected to JLR supplied reader equipment; we can't speak for any others
• Your dealer should know how to handle the problem
• Take your vehicle back to your dealer to have them deal with it

Recalling my ill tempered rant caused by the absolute denial of any problem by my dealer's service manager (let's call her Ms. Climate Denier for short) I was hesitant to return, but recalling the poor results the ancient Greeks obtained whenever they ignored the pronouncements of the Delphic Oracle, I decided to return to my dealer (plus I had an unrelated check engine light for oil level that needed attention).
Upon my return, I studiously ignored Ms. Climate Denier and worked with a new service tech who seemed both knowledgeable and anxious to help. I filled him in on the history of the issue and he promised to do some research. One day later, (JLR computers are always slow or down) he advised me that he had located and installed a gateway control module update that was supposed to address the problem. I'm not sure if the installed update was the general performance enhancement update that a number of posters here have mentioned or a different one. In any case, I picked up my car, enduring the searing gaze of Ms. Climate Denier all the while. If I was hoping for some acknowledgement that my issue was real, she made certain to subliminally burn into my brain that that was not going to happen. I drove my car for about 45 minutes to make sure the check engine light issue was cleared and to give the battery a good topping up. Finally, the moment of truth arrived and I parked and switched off the car. I put on its car cover all the while refusing to look at the tell tale emergency triangle. After about 5 minutes, I nervously lifted up the cover and peered inside. My eyes were greeted with ...No, not a glowing red emergency triangle or even the golden glint of King Tut's tomb but darkness and a solitary LED alarm flash on the dash - just as it should be when the Cat is sleeping
So, The software update seems to have resolved the issue - at least for my vehicle. All it took was escalating all the way to Mahwah and finding a service tech. who was willing to listen and help. As for Ms. Climate Denier - I hope you (don't) get bitten by an angry penguin at the Jaguar ice driving academy in Sweden.