ABout a week ago, my key fob stopped working. I was out of town, so thought I would just use the physical key to lock and unlock the doors until I returned home. However, the key would not operate the door locks from outside, as in, it would not turn over the tumblers when inserted as though it were the wrong key. But the key would still operate the ignition switch. Upon returning home, I installed a new battery into the fob and still the locks wouldn't operate. I tried pressing the door lock button while inside the car with the ignition on and still no response. Any ideas would be appreciated.
2004 XJR

 

My caveat is: I have not had an x350 door apart, although I have dealt with similar sits on an earlier coupe. So, there is some theoretical sprinkled in here, along with workshop manual guidance.

I want to make sure I have both instances understood.

1) When you insert the key in the driver's door, you CAN turn it. Both ways. But you don't hear or feel the usual feedback?
The door is always unlocked then, and pulling the handle does open the door ? (Obviously, or you wouldn't be inside.)

2) Pressing the door lock button in the car, does mean the central locker in the middle of the dash, NOT on the FOB ?

Okay, here's the deal:

As you hoped the door handle lockset is mechanically attached to the actuator. Sorta.

It's suppose to allow unlocking that door, even with a dead battery. The main 12 volt battery.

On the door's edge, you see the three torx bolts around the latch area. Those hold the electric actuator. The electric locking instructions themselves come from the DDM. Some of the rear door functions I believe are affected by the rear module.

To try and narrow the scope, I'd suggest a T-shoot.

Your initial comment was, that while away from home you felt like the FOB went pear shaped. Do you have any FOB function / response at all? Do any of the four functions respond? The light button? The trunk button? Any response if you push the lock button twice?

Back to the key and the driver's door:

If you insert the key, And turn to the left to unlock, Then within seconds, Turn to the right to lock, anything? If you have a window down, then insert the key, and turn to the right, and hold for a few seconds, anything?

Can you lock the door from the inside with the lever at the door handle, and then unlock with the key?

Do you ever hear any of the passenger doors lock or unlock? Ever?
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Most of this could be the result of a bad battery or the associated grounding for these modules or their plug-in connections.

That doesn't explain any mechanical key issues, though.

(I'm almost wondering if the actuator is stuck and not freewheeling. I just don't know, if that would give you the key feedback you're getting. Yet.)

 

I have replaced a number of door locks on my Jag.

The fault you have described is very unusual and I am afraid that you need to remove

the driver's door lock and maybe the exterior handle to determine exactly where the fault lies.

 

Or, you can take the key fob apart and replace the micro switches. Not a bad job.