Doors won't lock when shifter moved from Park

(Loren Engrav) #1

Intermittent problem with 97 XK8.
On moving shifter from Park doors do not lock.
And at the same time, there is a click under the J-gate when I step on the brake.
Thank you.


The click you are hearing is the solenoid operating allowing you to move the shifter out of PARK.

The doors should lock automatically when the cars speed is around 5 MPH and not when you shift from park.

(Loren Engrav) #3

Thank you but…

When the drive away door lock system is working properly, there is no click when moving shifter out of park. The click is only present when the drive away door lock system is not working properly.

Also, when the door lock system is working properly, the doors lock when the shifter is moved from Park even if the car is sitting still.

Thank you


“Not in park switch” most probably at fault.

(Loren Engrav) #5

Got it, thank you. Will suggest to “garage” that is the problem.

(Eric Capron) #6


It may be that you don’t hear the click of the shift interlock solenoid when the door locking is working because of the noise of the locks operating. Unlike S Type, 97MY XK8 does not have speed sensing door locking. It should lock as soon as the shifter moves from P. On my car you only have to move it a fraction and the doors lock and I tend to press the brake pedal and mover the shifter all in one go so I don’t hear the click unless I do the two separately.

I think the finger of suspicion does point to the not-in-park switch but there are other things it could be. There is a relay in the locking circuit that switches a ground to both door locks. You could check this next time the fault occurs by trying to lock the doors manually. If you lock the driver’s door and the passenger’s door follows, that will rule out the relay and its circuitry.

Shropshire, UK

(Loren Engrav) #7


Amazing how complex this is. But is true
If door locking fails on moving shifter from Park, and I manually lock drivers door, passenger door follows, is locked.

I would like to find a description of and repair of the not-in-park switch. But have failed. Any idea where I might find that?


(Eric Capron) #8

I have searched but can’t find any documented procedure for the replacement of this switch. It must be built in to the shifter assembly and appears to have its own connector which means that the plug could be disconnected and a temporarily bridged connection made thus bypassing the switch itself. I would be surprised if the switch is anything other than a standard microswitch that can be sourced fairly easily but I imagine that any commercial garage faced with this problem would replace the entire unit.

It is by no means certain that your problem is caused by this switch; it could just as easily be the wiring and unless you have the time and equipment to chase this fault down yourself it might pay to live with it until it becomes permanent when the cause will be easier to locate. You can spend a lot of money paying someone else to track down an intermittent problem.


(Loren Engrav) #9

Well I can do nothing but…

Lotsa posts say if you have a funky electrical thing first check out the battery. And simple tests are

  1. charge up battery; let car sit for 24hrs; see if voltage is ≥ 12.45
  2. charge up battery; leave lights on 5 minutes; see if voltage is ≥ 12.45.
    So I did both and battery passed and drive away worked.

But then…
I did the 5 minute light thing again, and immediately thereafter did another 5 minutes of lights on; so 10 minutes total. Bingo, drive away lock failed.

And, if you then drive away with the doors not locked, somewhere down the road the doors lock.

This is quite repeatable.

Since the car is not driven every day, seems quite likely that the etiology of the failure to drive away lock is simply depleted battery.

Sound true to all you pros at this stuff?


Fully charge the battery and see how long it takes for the fault to reappear. If you do not drive this car on a regular basis then a CTEK battery maintainer will be your best friend.

(Loren Engrav) #11

Hi Am in the process of doing this

(Loren Engrav) #12

Still continue to struggle with this. Seems to be
Keep battery charged > no problem
Let battery run down by disuse > problem appears
So simple answer is CTEK but is interesting
Issue seems to be
With or after run down battery, car does not know if shifter is in or out of Park
Is that a clue that might identify anything at fault?
Are we still looking at the not-in-park switch?