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🏴󠁧󠁢󠁳󠁣󠁴󠁿X260 R-Sport in Aurora Red
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Then why with the older cars did they have the niche for placing the key in to start the car if the battery was dead?
It’s an inductive loop , all xf‘s have it, it’s to power the pcb in case of a dead battery.
 
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I think you're both right in some ways.

While in normal operation, the battery in the fob is required to operate the buttons, keyless entry and normal security enablement of the car/ignition, the transponder is a backup and only really used when they fail. That's why you had to push it into the slot in the older cars (and often never be able to remove it ever again :ROFLMAO: ). Newer XF's I believe you had to hold it somewhere close in the same area to do the same job while it read the passive transponder.

If the transponder was needed all the time, how would it ever work if the key was in your pocket (on keyless entry/start models).

Presumably because you haven't disabled the security up to this point, the alarm will be going off until you've pushed the key into the slot, and pressed the engine start button.
 

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Discussion Starter · #27 ·
Looks like it is the supply wire for the accelerometers. If you have the wiring diagrams just search for spl872.
View attachment 195841
Omg thank u and I can't believe I didn't put 2 and 2 together lol assuming of course SPL is for splice lol I've probably looked right past that and many others several dozen times in the last week
Thank you again.
 

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Discussion Starter · #28 ·
The battery is there to power the pcb (the buttons)
The transponder is totally separate and unconnected and can look like a wee square bit of plastic or a capsule type thing, so when you get the fob battery low message, it’s just telling you that the buttons might stop working.
That would explain why when ur battery is dead u can still start the car by holding up to the emergency starting location.
 

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Discussion Starter · #29 ·
I think you're both right in some ways.

While in normal operation, the battery in the fob is required to operate the buttons, keyless entry and normal security enablement of the car/ignition, the transponder is a backup and only really used when they fail. That's why you had to push it into the slot in the older cars (and often never be able to remove it ever again :ROFLMAO: ). Newer XF's I believe you had to hold it somewhere close in the same area to do the same job while it read the passive transponder.

If the transponder was needed all the time, how would it ever work if the key was in your pocket (on keyless entry/start models).

Presumably because you haven't disabled the security up to this point, the alarm will be going off until you've pushed the key into the slot, and pressed the engine start button.
U seem to have a great knowledge of the keys and so maybe u can help with my one of my keys that only works to start the car so does that mean the kvm doesn't have it in its memory or is it the instrument cluster doesn't have it on its key ring? I have both original fobs that came with the car but only works both sides of its job and for some reason I'm not seeing the 2nd key won't function the security side.
Any thoughts or insight would be much appreciated, it is only my back up key but I would still like it to be fully functional
 

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Discussion Starter · #32 · (Edited)
So today I began my journey testing the 3 accelerometers and 4 height sensors, I won't get into the numbers they produced because they all showed equal values regardless of the test performed and I did several for each. I then said screw it I'm down to what two possible solutions 1. Being the module itself is cooked like a goose or 2. My CJB isn't putting out the power that it needs(I would have to figure out why later). I went in grabbed my spare battery that had a charge of 12.86V and I hooked it up to the module and sure as shit when I hit the on button there was no more adaptive dynamic fault and no E-DIFF fault and believe me I stared for a good several minutes just waiting to see them pop up. so if understanding this correctly that means the module is not dead and i now need to figure out why the CJB is only pumping out 7 and change volts when the car is running.

Any suggestions on where to look or if it's even possible to hook that module up to a temporary power source safely until I get this sorted?
I just configured the CJB as new module the other day and it seems all that did was disable my windscreen pump(which i expected to happen)give me full function of 1 key fob, it still has ????? for the vin and 2 others. I obviously wasnt expecting the CJB to be completely cured of its sickness but i mean damn by my calculations i ended up worse off as i lost partial functioning of a fob and my washer pump. Did I have high hopes in thinking it would fix the issues it's been causing? Or at least be in a better state than before the programming?.
This cjb is really starting to remind me of my wife hahahaha
 
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