Grand Cherokee WJ - Alarm will not disarm

[Hoover.]

I think I already know the out come is death to the old girl...... so hopefully with your help we can get her back to health.

Car unlocks but the alarm will not disarm, and cannot turn off the alarm once it is sounding..... vehicle will start and drive with alarm still going.

I've tried the following:
new batteries in remote
manually unlocking
disconnect/reconnect battery
various different sequences of pressing buttons on the remote etc.

Two local car specialists will not touch it saying they don't have the diagnostics..... what happened to good old bodge it, I'm the customer and I am telling you to do it :humph:

Trouble started a few weeks ago, when the car had been sitting for a month without use, opened it up and the alarm went off, I thought it was because battery was low, left it running and somehow the car locked itself with keys (only set of keys and remote) in the ignition and running ..... had to break in with a coat hanger to open electric window to gain entry...... took it for a run to charge battery, no problems for the rest of the day.
The following week alarm went off again when I opened the door to get in, took it for a run no problems agin for rest of day.
This week end opened her up, opened door and alarm goes off eventually get it to shut off after taking it up the road with alarm still going. Took it for a 50 mile run with no issues... back home, went to use an hour latter alarm goes off... now at the stage where the alarm armed constantly and cannot be turned off.

Any ideas on how to fix or permanently disarm the alarm...... I've searched the net and can only find fixes (that I understand) for previous models...... Please keep advise in laymans terms.

[richs2891]

http://www.jeepforum.com/forum/f310/disabling-wj-a...

may help or give you some pointers.

I had random alarm issues due to dodgy door (light) switches. It may be worth checking yours work or if can live without the light coming on when open door.
Temp fix would be just cut the wires to the alarm unit ?

[SlimJim16v]

It depends how much a part of the ECU it is. If it's an add on, you can trace the wires from the alarm and remove and reconnect where needed. You need to know what you're doing, so if not, an auto electrician or alarm fitted should be able to do it in about 4 hours.

[richs2891]

Given the age and fact that the OP states can start and drive with the alarm going does not sound to be very tied to the ECU. Most likely a importer / dealer fit item, tied to the central locking.

Your correct any decent car sparky should be able to sort it pretty quick, but I think I would be having the drivers door cards off first and checking for obvious loose wires / broken door switches / damaged or corroded earths.

[SlimJim16v]

Yep, you're correct. I should've read it properly, so will be much easier to remove.

It may be what you've said, so worth a look. Another possibilty is if the alarm has a battery back up. Alarms can do strange things when the rechargeable batteries die, mine did.

[stevemiller]

Had this problem fitted new Battery (The big one under the hood) problem gone! It took some time to get to this I have to admit.

Regards

[Hoover.]

If you mean the battery that powers the who car mines new, only fitted 2 months ago.

Bought a replacement alarm module with sensors, so hope fully will have everything to sort it this coming weekend.....rather then just pull the door cards off and find no broken wire.... it was only £30 incl postage, can always sell it on if it is just a broken cable.

I would be nervous about just hacking the alarm out, as it is supposed to be working with the main ecu (from what I have read).

This hopefully will turn into one of those jobs where my neighbour takes over after about 5 mins, all I do is make tea

[Steve_F]

I've just sold my old one, the battery in it was absolutely shot and the alarm didn't do anything strange at all. Obviously will be different in different cases but certainly didn't cause my alarm to go off.

The only time it did was a very windy night and the food waste bin was across the other side of the drive resting against the Jeep.

[Hoover.]

Poxy weather

[Hoover.]

well for now I have disconnected the key central locking system (which arms the alarm) and taken the remote central locking fob off the key ring... so I can now manually unlock the drivers door (only key entry on the car) and then flick the electronic central locking switch in the car to open the other doors/boot....... not perfect but at least it is driveable actual chuffed with my self for achieving this

now where is the alarm module hidden....... I think we have a different set-up to our American freinds

[tr7v8]

I'd have a word with Terry at A1 Chrysler in Higham nr Gravesend Kent.
He fettles mine & has worked on 'em for 20 odd years so knows their foibles.

07437583783

[Hoover.]

Thanks for that ..... I'll put that number in phone book, and will have chat with him after Xmas as few other things need doing.... just been offered a V8 though, which is tempting as I could swap all the nice bits off mine over and out mine

[scrwright]

Just in the process of doing the same with mine, 4 litre is getting broken up, shiney stuff going on a v8