Not that I really mind, but as my car is still under original warranty for a few more weeks, I'm wondering what might be the culprit? It used to stop at red lights all the time, especially if I pressed on the brake hard. Lately it has not been shutting off when stopped, even if I try by pushing hard on the brake pedal.

Im guessing the battery that runs the auto stop/Start could be dead, but I assumed there would be some idiot light telling me this?

 

Mine does the same thing no warning on dash car never shuts off, take it to the dealer I read on here most of the time a module needs to be flashed/updated.


If you unplugged the battery in the trunk you would get a SS system unavailable message.

 

Below are some items that can inhibit Stop/Start to work. There are other ones as well, such as air/fuel ratio could affect it. Since you still have warranty, I would take it to the dealer and get them to check it. First thing they should be checking is the battery. If it needs to be charged, they should charge and retest. If it comes back and says charge and test again, the battery will need to be replaced. If the battery gets replaced, they will have to reset the BMS ( Battery Monitoring System ) with the diagnostic machine. If it turns out to be something else, there is a test they can run through the SDD to pinpoint what the problem is and go from there, but definitely take it in now while its still under warranty.


I have pictures from a test I did last year to give you an idea, but I will have to post them later today or tomorrow.






Auto Stop/Start System Inhibits


The inhibit conditions listed below will not set Diagnostic Trouble Codes (DTCs) but will set flags which can be viewed using the Jaguar Land Rover approved diagnostic equipment - Datalogger / Powertrain Control Module (PCM). Normal auto stop/start system operation will resume when an inhibit condition is no longer present, but the battery related inhibits may persist for some time.
NOTE:
Do not reset the Battery Monitoring System (BMS) to rectify battery condition inhibits. This may temporarily restore auto stop/start system operation but will lead to a recurrence of the fault.


Inhibits

• Auto stop/start off switch has been operated by driver
• Transmission not in neutral
• Hood open detected
• Driver door detected open
• Driver seatbelt not fastened
• All terrain progress control special programme selected
• Climate control demand exceeds calibrated threshold
• Heated windshield operating
• Trailer connected
• Brake booster vacuum below threshold
• Engine coolant temperature below threshold
• Engine oil temperature below threshold
• Battery state of charge low
• Battery cold cranking capability below threshold
• Ambient temperature above 40°C
• Ambient temperature below 0°C

 

I, for one, would have it fixed. You never know what else they may find.
But I would then deactivate it as described in various posts on this list.
You want to know why it stopped, and doing it yourself would provide that info.
================================================== =
You dreamed of a big star -
He played a mean guitar -
He loved to drive his Jaguar...

So welcome to the machine

 

Below is a picture of the screen while performing a ECO Stop/Start test to see what is actually causing it not work. You can see what " Driver " influences, and what "Vehicle" influences cause this. Hope this helps, but I would definitely get it sorted while you have some warranty time left.

 

You can see that the Air Fuel Ratio on that one was affecting the Stop/Start from working. All I needed to do was take it for a drive. Sorry didn't get a proper picture for the items on the far left, but they are just various temperatures, such as engine coolant, trans temp, I believe ambient/outside temp, rpm and vehicle speed. The middle column you can see the separation. Most of the time I've had complaints, its been the one that says " Power supply auto stop/start system ", this has usually been an issue with the battery, either because the car isn't driven enough to keep the charge up, or the battery is at fault. This is why the battery has to be tested first before anything is suspected.


On another note, keep in mind that when replacing the main vehicle battery, make sure you use a AGM ( Absorbent Glass Matt ) battery. The lead acid or calcium batteries can not handle the stop/start system, and the battery will go dead, I've had to customers try to cheat because of the price of the battery, and wound up back at the dealer.

 

Just a heads up, the previous owner had replaced the battery with a interstate group 49 lead acid, I called interstate since the battery was only 10 months old and they let me swap and pay the difference for a group 49 AGM battery.

As soon as I installed it, drove around the block start stop working now.

 

Hello Guys,

if anyone can help me with the right advice.

i bought Jaguar XF 2 months ago and due to my previous car wasnt sold so i didnt use my jaguar for 2 months.

since i have start using it start/stop Eco system is not working,

can some one advice please how to get it solved ?

some one advices maybe battery is low so just drive for few weeks it will start work automatically is that true ? or do i have to take it to jaguar workshop to get this issue checked ?
car is not in warranty i wonder if they gonna charge me alot over this issue but i dont know when last time i checked it was working fine

some one help please.

Thank you,

 

I have the the exact same problem . . . Did you manage to sort the problem out ?

Cheers Ian

 

Yes the small battery in the boot(not the large car battery the one beside it) needed to be replaced

 

Wonderful ! That makes sense. I have ordered a new one THANKS

Any problems changing over, or just disconnect and connect new one ?

Ian

 

No problems when we did it. Hope it goes well for you.