I've looked through several threads on the subject, but can't find anything the same as the problem I'm experiencing.

A few weeks ago I noticed that when I unlocked the car using the fob, the central locking would cycle four times. It seems to be all the locks doing it and it was intermittent. The problem seemed to get better after I used it a bit.

Yesterday I unlocked it and it all cycled four times. When I put it in gear the doors lock OK, but when I selected park and opened the drivers door all the locks cycled again and the internal handles were flicking from locked to unlocked. Clearly the problem is getting worse but I'm not sure where to start.
As usual , any help would be appreciated.
Thanks, Andy

 

Failing or sticking door lock micro switches could possibly cause that but I've no direct evidence to back it up.

Graham

 

Hello Andy:
There have been at least 2 times on this forum where the culprit was a blown (or bad connection) fuse # 15 on either the driver or passenger fascia fuse block. At any rate, it is a quick check of these two fuses. Good luck.

 

My XJ6 locks have the same problem frequently, but I have ignored it so far. If you find a solution I would give it a try.

 

Mine has done this intermitently since I have had it (two and a half years). It is doing it at the moment, but from previous experience, it will probably stop doing it for a few months. It has been suggested to me that it may be due to the state of the battery, but it does it regardless of whether I have just completed a long run, or the car has sat for a week.

 

The most common cause of this problem is a bad microswitch in the door latch mechanism.

That being said, weak battery problems usually have little to do with whether the car has been sitting a week or was just driven. What happens when you have weak battery (which needs to be replaced) is that during starting the voltage goes very low (perhaps 5-7 volts or so) due to the high starting current. This exposure to low voltage then causes one or more on-board modules (read computers) to begin to malfunction from that point on until it is reset.

 

Thanks for your input everyone. I took the car out for a drive yesterday afternoon and it did the now usual cycle four times bit. When I got back an hour later, I locked and unlocked the car several times and everything was perfect.
So......I'm wondering if this is a voltage issue and a C/L module having a minor hissy fit or as Graham suggested, perhaps a dicky micro switch in the door, but if so, which one?
I think I may try a hard reset (thanks Steve) and see how it goes.

As an aside, I was looking through JTIS and it says that for the MY2001, when you use the lock button on the fob twice in quick succession, the car 'super locks' and any open windows will close. I experimented with that and my windows don't close. Any ideas?

Thanks as always,

Andy.

 

Andy,

The security features vary from one market to another and also certain features can be enabled or disabled by the dealer.

On your 2001 MY UK Spec, the second press of the lock button within 3 seconds deadlocks the vehicle:



(click on the image to enlarge it)


The window close function only operates with the key:



(click on the image to enlarge it)


The above sections are from the 2001 MY Driver's Handbook for the UK. If you don't have this, you can download it and the other Handbooks in the Document Set for your vehicle from this link:

https://www.jaguarforums.com/forum/x...-2003-a-67827/

Graham

 

Hi,
My 97 XK8 is doing the same, cycles lock/unlock 4 times when unlocking, locking or as you drive off. It is very annoying.
It is not the battery, I have a new one, fully charged, and I'm an electronics engineer who works with batteries - that is not the problem.
The problem has come about after winter storage this year, but i had hoped would go away as things dried/warmed up.

I have tried to isolate the side, as the 2 lock ECU's are fed from the fascia fuse boxes on each side, however the right (drivers side) one seems to be a master (probably because of outside lock).
As far as I can see from the wiring diagrams (thanks whoever posted these) the same microswitch appears to serve the window 'drop' function and to show door position - these all work. Unless there's a switch I have missed.
I don't really want to pull all the door apart, and the lock/security module is right at the bulkhead behind the radio, so a major task to get to.
Anyway, if that failed, the whole thing would be dead, this is too consistent, I would think something designed in by Jaguar to signal a fault to technicians, to make it easy to isolate.

Anybody seen this/fixed it/has an idea of the sequence of operation?
many thanks,

 

I had a slightly similar problem on my 2001 XKR. Door locks would open after a few minutes driving and would cycle. Then, the security alarm would cut in randomly when parked. It took the main dealer 1 week to track the fault down. Initial diagnosis (sensible) was a faulty door latch but made no difference after new one fitted. Finally, turned out to be a duff security module - not cheap. Since the new one was fitted (and all my keys reprogrammed) its been fine.

Just a thought.

Steve