Hi Rob and Ragjag,
Thanks for sharing your method. I tried it out and it didn't work exactly the way you described but here is what DID work:

1. Battery hooked up and beeping and flashing
2...Enter car and swich in II position. Pressed remote 5 times and nothing happened.
3. Returned key to "0" position but left in place.
4 Pressed the remote five times- each time the remote was pressed the horn beeped.
5. And the beeping stopped. I removed the key and left the car and blessed silence!!
Now I can leave the car with the battery cut off switch disconnected so I don't have to worry about fire prevention.
What a reliefe!! Hope this works for you as well. Now I have to attend to front end alignment. The XJS Service manual has figures for castor, camber and toe-in in the XJS 3.6 and XJS- 3.6 section but there is nothing in the 4.0L section so I assume they are the same. My car pulles a little to the right on the road and I notice that the right front wheel is toed out excessively and has negative camber. I've been told that 1/8" toes in is best.
Thanks again for your messages and happy motoring!!
Jim S stix66rb

 

Dear XJS owners, I have a question: Do the later XJS engines (4 L) have hardened valve seats and if not, is there a problem with valve seat erosion using unleaded gasoline (petrol).
Thanks,

Jim S stix66rb

 

Jag engines have used hardened valve seats for decades....since the late-60s I think.

You'll be fine with unleaded fuel.

Cheers
DD

 

Thanks Doug, That is a reliefe!! Something less to worry about.

Have a great day and thanks again,

Jim S stix66rb Cedar Rapids, Iowa, USA

 

For the win:




Well the beeping and flashing has been cured - more through luck and last minute exasperation than anything else.

Here's what I did (and yes it seems to be a hybrid of every comment above)

1. Unlock all doors and boot manually.
2. Disconnect the battery.
3. Leave for some time (I'd left it overnight)
4. Reconnect battery
5. Insert ignition key
6. Press fob five times in quick succession holding it close to the steering column. The bulb out warning light on the dash flashed five times

The beeping stopped!

Then deactivated the immobiliser as normal and car started.

Interestingly the central locking now runs off the fob which it never did before - even with a new battery.

 

How the heck do you disconnect the white plug in this picture? I'm desparate to get this thing to shut up and I've tried the different options so far and haven't got this thing to quiet down

 

If you mean how to physically wrestle that thing apart?

The first time, I think I had to use two pairs of pliers. Later, the plug became slightly more amiable, and I only had to keep a single pair handy to compress the clip side of the plug to separate. I honestly wondered if it would ever come out, but it did eventually.

 

Yes precisely! I have a 1993 XJS and this pic looks exactly like my setup, but am having a heck of a time disconnecting these wires and I don't want to break anything. Also, that's a lot of wires hooked together and I'm wondering if this affects anything else besides the alarm? All I want to do is get the incessant beeping to stop when I turn off my car in some other way besides disconnecting the battery. My FOB doesn't work and I could care less about having a functional car alarm. I was checking out the alarm horn and am wondering if there are some wires to it I could cut. Thank you much for the help

 

DONT cut anything...get it sorted out. The plug is not to hard to separate. It does affect the remote door locking if you unplug it. Try getting a remote that works.
Also read the answers on the other alarm thread about your model year and where the valet switch is ?

1 where are you
2 what car

 

I'm in Phoenix and my car details should show up now in my signature. The title says it's a 93, but I do have that on/off butterfly switch on the steering column that is the valet switch? What does it do? Can it help me turn off the beeping?

I tried looking under the hood and it seems like the alarm horn is buried in the front somewhere so nixed the idea of trying to remove it. We just got this car so have a million questions, but right now I'd like to just stop the beeping. Buy a jag she said, it's a great deal and so pretty she said... I knew there would be headaches so take my complaining with a grain of salt.

 

OK, did the car work fine before the new battery ?
I think I would spend $130 on a new remote before I ripped the wiring apart.

push the valet key to off

 

" She" has good taste in automobiles!
The valet switch on, the green valet key will lock but will not open the glove box where you have placed her jewels. The attendant is now driving your jag away at 100 miles per hour, but don't worry he can't open the glove box!

I have an early 1993 with inboard brakes. Later '93s had outboard brakes. I used the 1992 alarm reset and it works. I do it all from the trunk; disconnect the battery wait a few seconds reconnect the battery press the fob button 5 time and the fob has been reeducated. More than one fob alternate back and forth until you have pressed both fob for a total of five times. (not each fob 5 times) If you have the Jag radio you will have to enter the code. Once you set the fob it will open an lock the doors, gas tank, and trunk. it will also set off the emergency system if you hold the button in, but it won't work with the valet attendant who is now on his way to Nevada to sell your car and head for Los Vegas. One push wiil turn off the emergency horns. If the locks don't work, remote or no remote, see my posting on easy lock repair.

 

You will need 3 hands. push in where shown and pull plug apart. Maybe will need help with a small screwdriver also where shown.

 

MALC4c
Great explanation, but what is a "Nudge Control?"
The alarm antenna is shielded by the trunk. That seems to be the reason for the complaints on operating distance. It also explains why I had no problem arming my fob. I was right next to it and the trunk was open!

 

This thing. sets the alarm off if the car is bumped or nudged

 

Never knew it was included in the XJS. I'm gonna nudge my car tomorrow and see if the alarm goes off. I take it you mean shake the car as in testing the shocks; yes?

 

It senses if the car is bumped.
If fitted it should be visible behind the rear light at the bottom of the alarm. It has a screw to change the sensitivity. Behind that is the backup battery.


Oh and a little piece of info.......If you plug the 2 yellow wires on the loom together the alarm will auto set after leaving the car.

 

Nudged the car but no alarm. But the shocks are good!
Have Nudge Box but didn't see yellow wires
1. Can lock and open car with fob; open doors and trunk no alarm
2. Can lock car with fob and unlock drivers door or trunk with key; open either alarm sounds
3. Can lock car with fob but cannot unlock with key from passenger side
4. Fob locks on third press and opens on forth
Don't think the system is correct, but since I understand it, I can work with it...

Your thoughts

 

Hey so thank you to the above posts as I finally figured out the alarm. I had to keep trying different batteries for the FOB until I found one that was good and presto I heard the five beeps and the alarm stayed quiet. Much thanks for the diagram info as I still would like to just unplug it and anything else that can cause a drain on my battery. Currently, I have to leave a trickle charger connected to the battery or else after a week the battery will be completely dead, but I'll look for some posts out there that discuss electrical issues. Thanks again :-)

 

Glad it worked. The trickle charger is a normal thing on our cars if not used every day..