Activate alarm problem

[whitehead70]

Just started today on 1998 XK8 convertible, purchased in December.

Every time i use the fob to lock the car it gives the beep sound that in the past has meant that a door or boot lid was ajar.

Checked all the doors/roof/windows/bonnet/boot etc and seem shut.

Is there a way to tell which particular sensor it is copmplaining about?

It is kept outdoors, not sure if the recent weather has played a part in some way.

Any help appreciated.

Thanks

Neil

[mike020150]

In the current weather, it's possible that water/ice is affecting some part of the various latches/microswitches. Have you tried locking the car mechanically with the key to see if it responds differently and gives you any clues? Is the bonnet shut properly? Do the courtesy lights operate correctly when doors or the boot are opened? Failing clues gained from those actions, the car probably needs to be interrogated electronically by a garage with either the JDS or Autologic diagnostic system. Mike.

[whitehead70]

Hi Mike, thanks for the reply.

Courtesy lights come on with both doors (pointing to boot/bonnet maybe? Repeatedly opened/closed though)

Using the key activates the central locking but get the same beep sound when doing so leading me to conclude the alarm has not set.

Battery seems ok.

Garage it may have to be.

Neil

[MyQuest]

Neil, I guess a simple way of checking if the alarm is activated would be to unlock the door with the key and wait several seconds.
If no alarm - then not activated! The book says if unlocked in this manner you need to get the key in the ignition within 7 seconds (I think) and turned to prevent the alarm.

I assume the warning you are getting is a longer 'chirp' than the standard short locking one?

Michael

[whitehead70]

hi Michael, thanks for the response. Definitely not alarmed as I don't need the key in the ignition after unlocking.

Tried disconnecting the battery and reconnecting after seeing something relating to that on a posting. Still no luck.

[deltasierra]

If a door is open there should be a message on the dash telling you which, if not then open each in turn and see which sensor does not show a message. If all give an open message it could be seized/ frozen mechanism in a door, if the mechanism works check the wiring particularly the connector plugs.
PS keeping a convertible outdoors is going to cause electrical gremlins

[whitehead70]

Tried all the doors/bonnet/boot etc as per your advice, all report correctly on the dash.

Got it booked in for jag specialist to run the computer on it.

Well in only my second month of ownership i hope it doesn't cause too many gremlins keeping it outdoors or should that read "keeping a Jag convertible outdoors is going to cause electrical gremlins"

Not been an issue with previous jap convertibles, celica, mx5, mr2

Here's hoping for a good summer!

Neil

[J44EAG]

I keep my 02 S-type out doors and this can play havoc with electrical connections. The S-type "electrical architecture" is based on the XK8 system so the operating systems and connections are very similar and closely related.

If ever I experience an electrical gremlin on an S-type, from experience I always suspect a multiplug connection issue near to the offending service. Door lock plugs and throttle body connections have been often found culprits.

A good clean up of the relivant plug and a smear of good electrical grease often sorts the problem out. Being high current units, door lock solenoids frequently exhibit this fault. The clean up gets things going again on many occasions. As Dave Marks would say, "check the basics first".

The other cause of gremlins is the tired battery scenario. Jaguars fitted with high tech electronics seem to rely on good voltage of around 12.8v off load to function well. Duff batteries have in my experience caused problems with locking and alarms, flashing headlights and irritable window operation and wipers that go bonkers!.

In addition, disconnection of the battery can also clear down the faults frequently found but perhaps unknown unless interogated by an Autologic or similar unit. On my S, a defective throttle body loaded the computor with fault codes. Having changed the body, disconnected the battery for 20 minutes, re connected and fired up again, ancilliary systems operated more efficiently and I have not had a problem since. Cost to do it? Nothing, just half an hour with a spanner. Don`t forget to have the radio code to hand. You will need to reset the radio after battery disconnection.

For me, an occasional clean up and clear down works well. I suppose it is a bit like a disc clean up and de frag on a computor. Blows out the fluff and feathers!

Give it a try. You might be pleasantly suprized.

Mike Kennedy, S-type Co-ordinator

[whitehead70]

Hi Mike, thanks for the tips, good advice all round.

I did try disconnecting the battery after reading it on a post somewhere but didn't do it for as long as 20 minutes, will give that a go.

Failing that it is going to an indy garage for the tensioners soon so it can get hooked up to the diagnostics then.

Thanks,

Neil