Alarm Going off intermittently (recently on a daily basis)

[bikermick]

Hi there,
I have a problem with the alarm sounding randomly on my 98 XJR!
It was very intermittent for the past 6 months but now happens on a daily basis
I recently purchased an Autoenginuity Tool with the Jaguar enhancement which seems to give me conflicting information but I think it has helped me narrow the problem down to the front passenger door as the culprit.

Can anyone give me any advice as to what could be the cause of this?

Regards

Michael......

[joejag308]

Michael, i have sent your problem to David Marks as the alarm system is a complicated area with all sorts of faults......wiring , bad contacts, ....however one quick test i usually try is to disconnect the battery and leave off for an hour or so,or even put it on charge over night then put it back on making sure you have your radio code to hand.
Also make sure your boot lock works with the key too.........Joe

[bikermick]

Hi Joe,
Thanks but I already tried that I took the battery out and charged it over 2 days last weekend just to rule it out. The battery is showing 11.9 volts first thing in the morning with the ignition on before starting it. Does that sound okay to you?

Michael......

[joejag308]

Michael......i dont any tech details re the battery levels ....it was just an idea to try .....looks like you had the same idea..........it could be so many things, some of the causes for the alarm going off ad lib is amazing.
I have asked for any ideas from guys with the same problem so keep watching this space as they say.........Joe

[joejag308]

Michael your alarm enquiry................Dave Marks replys.............

Hello Michael
>
> if you are confident in your diagnosis, the logical way forward
> is to replace the latch module as a microswitch within this is
> almost certainly the fault, assuming no broken/rubbed wires or
> poor earths.
>
> this sort of alarm activation is not unusual.
>
> It may be, if you have the knowledge that you can strip down the
> latch module and see about changing the switch within but I have
> never done this as on a commercial basis, it is not worth while.
>
> Hope this is some help
>
> Mail back if required
>
> Regards
>
> David Marks
>

[bikermick]

Hi Just an update on this.
I have traced this to a door check strap problem and although the door looked fully closed it was obviously not. I have been ensuring I checked the door was closed properly after anyone was in the car and the alarm hasn't gone off at all since my last post to the forum. I have a new check strap to replace over the weekend so I will let you know if it resolves it.
Thanks to all for the help and advice.
Much aprreciated

Michael.......