Immobilizer question (manual disarm)

[knucklehead]

Greets all.
First time caller, long time listener. Great forum here.

Recently acquired a 97 XJ Limited (came from a Sport, so I think I'm
moving up in the world ).

This one has some 'fancy' bells and whistles including an 'immobilizer'.
Immobilizer is off when I open with the key FOB and it gives me a few
mins to start the jeep. If I wait too long "Security" light goes on in the
dash and i have to disarm again or it won't start.

So far so good but I have a nagging feeling my key fob batt will die
when I'm in the sticks and I won't be able to start the jeep.

Is there a manual "disarm"? IE without using the remote?

This XJ also has a fancy overhead console. Above driver's shoulder
there is a silk-screened graphic that says "disarm" -- i tried pushing
it but it does nothing.

Just kidding. But I assume I can wire a switch in to disarm.. just not
sure where the wires go.

Any help greatly appreciated.
Thanks!

PS Bonus question: "CRUISE" light is always on but I don't have
cruise control. Seems a little silly and is bright as the sun when driving
at night. Is this is a sign of something or can I just pull the bulb?

[anthonygubbin]

Originally Posted by knucklehead

Greets all.
First time caller, long time listener. Great forum here.

Recently acquired a 97 XJ Limited (came from a Sport, so I think I'm
moving up in the world ).

This one has some 'fancy' bells and whistles including an 'immobilizer'.
Immobilizer is off when I open with the key FOB and it gives me a few
mins to start the jeep. If I wait too long "Security" light goes on in the
dash and i have to disarm again or it won't start.

So far so good but I have a nagging feeling my key fob batt will die
when I'm in the sticks and I won't be able to start the jeep.

Is there a manual "disarm"? IE without using the remote?

This XJ also has a fancy overhead console. Above driver's shoulder
there is a silk-screened graphic that says "disarm" -- i tried pushing
it but it does nothing.

Just kidding. But I assume I can wire a switch in to disarm.. just not
sure where the wires go.

Any help greatly appreciated.
Thanks!

PS Bonus question: "CRUISE" light is always on but I don't have
cruise control. Seems a little silly and is bright as the sun when driving
at night. Is this is a sign of something or can I just pull the bulb?

I was under the impression Limited's had cruise?? Has yours been removed? Also what key do you have? I was under the impression also that the key triggers the off switch for the immobiliser. 96 ECU's should be cheap enough might be easier than trying to dodge up something that might let you down when you least need it. Most 96 ECU's I believe don't have the immobiliser.

Regards A

[rainman]

post updates are not my thing, however i believe that the immobiliser is built into the pcm and there is no magic wire that disconnecting will neutralise it.
maybe a spare battery for the fob in the centre console?
good luck with it.

[Escapable]

Originally Posted by knucklehead

This one has some 'fancy' bells and whistles including an 'immobilizer'.
Immobilizer is off when I open with the key FOB and it gives me a few
mins to start the jeep. If I wait too long "Security" light goes on in the
dash and i have to disarm again or it won't start.

So far so good but I have a nagging feeling my key fob batt will die
when I'm in the sticks and I won't be able to start the jeep.

Is there a manual "disarm"? IE without using the remote?

Any help greatly appreciated.
Thanks!

The function of the immobiliser is to do exactly that - to prevent the vehicle going anywhere when it is unattended. If you leave the vehicle with the keys removed (or not inserted in the first place) it will immobilise after a time and you will need to push the button on the FOB.
It will also immobilise if you disconnect the battery.

The battery in the FOB has lasted me over 2 years and you will notice it dying as it will lose range to activate/deactivate but will still work up close - there is no history of immobilised cars lying on the tracks with flat FOB batteries (available anywhere). Put a new one in and relax.

There are many posting regarding how the alarm/immobiliser works.
The remote sends a code to the "Wireless Receiver Module (in the door or overhead) that detects and checks it is correct and then lets the PCM know (via the vehicle CCD bus) that it has received a valid code and the PCM deactivates the immobiliser (internal to the PCM operation): this involves allowing the injectors to operate, otherwise the return from the injectors does not happen, thus no fuel into the cylinders and no go.
As this is all done via the CCD bus and the PCM so there is no magic wire to disarm. Opening the vehicle with the key will unlock the doors but you will need to push the FOB button to start.
This is all reflected in the stats regarding vehicle thefts.. Jeeps are not on the major list...
and NO, you cant access the immobiliser from the OBD bus (the dealer tools access the CCD bus).

[junglejuice]

Ok we need some more info on your vehicle as 97 was the changeover model between pre and post updates, does yours have quarter glass in the front doors?
All limiteds to my knowledge had cruise control and ABS....

[rastus2571]

There's been quite a few threads on other forums I go on about how to disable security systems. It just makes me wonder, that's all. And a lot are first time posters. Don't take it the wrong way but it does worry me at times. This may not be the case. So don't be upset.

Sent from my HTC Explorer A310e using Tapatalk 2

[Roler]

I've read quite a lot into the immobilizer issue, because mine is playing up every now and then. To the point that it almost left me stranded. Luckily this has never happened, but I came to the point I really wanted to get rid of it. Long story short, the above mentioned/explanations are correct. The immobilizer feature is in the PCM and can NOT be (custom) disarmed of by-passed. There are sad stories of XJ's needed to be brought to the JY because the immobilizer would no longer disarm, leaving the Jeep useless.

The only theory that would possible work, is to source a PCM without the immob feature from overseas, from a country that did not have the immobilizer required by law (as we did apparently). Not come across someone who has tried that though.

Mine is ok,for now, but I know this is the only serious pending doom thing I have going on the back ground which has no fix.....which is always a bit uneasy, especially when off-roading (had it one time play up when on the beach with upcoming tide...not cool, I can tell ye).

Good luck with it.