kody24

I'm on my second zj and this is the first time I've had any issue with an antitheft device, I just did a tranny swap and when I hooked up the battery I got the cool flashing headlights. I looked up how to disable it with the key, but I have always hated antitheft devices and want to either disable or eliminate it. I found a youtube video on it, but the guy looked more than a little methed up. Is there a proper way to do this before I end up stranded or locked out because of this thing?
Just for clarification, I live in an area where we don't lock doors and leave the keys in everything all the time, so this thing locking me out is a legitimate concern.

Muddz

I've seen several methods to disable but haven't really found anything that appears to be thorough and legitimate as if the people know actually what they're doing.

One method was to ground a door sense wire that tells the passive security system the door is ajar or opened, So the VSS won't activate the itself.

I can't remember off-hand other versions which aren't very well described.
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Can the VSS module be removed? Possibly remove a fuse or cut a power wire to the VSS module.

I have a Jeep OEM Anti-theft FSM in paperback it does go into detail how to describe, diagnose and repair the VSS.

What my VSS did one time. I was helping a friend all day long work on his 92 Laredo with my tools in my 95 ZJ and the rear hatch open.

At the end of day, dusk, I went to start the 95 ZJ and all I could here was some strange sounds coming from near the engine that sounded like it was coming from the starter solenoid. The engine woundn't turn over or start and the head and tail lights began flashing.

I thought perhaps the battery was low so after resetting the security with the key fob, we tried jumping the 95 ZJ (4.0L) and the same thing occurred, engine wouldn't start and headlights started flashing.

After reading through the FSM manual I found a section that described when the battery is connected and then reconnected the VSS will become active flashing head and taillights and at the same time the PCM will disable fuel to the injectors so the engine won't be able to start.

After leaving a battery charger on the battery for a couple of hours I went back out and tried starting the engine again this time after ~30+ seconds of cranking the engine started and the VSS wasn't active.

kody24

That's the kind of thing I'm trying to avoid. My searches also turned up sketchy methods that I would rather not do.
I'm reluctant to just dig into the dash and remove it because I'm not sure if it has to be there to make things function or if it's as simple as removing it and jumping a few contacts in the plug. I currently have a parts rig so I could pull the unit out of it, open it up and disabe it by removing the contacts at the plug, then soldering in any jump wires needed before installing it. But first I would have to know which anonymous box it is and which if any wires need to be jumped.

Muddz

What year is your Grand Cherokee?

Here are a couple pics for a 95 ZJ for what is called a "Relay Center". The relay center is located in different locations depending on the model and year. My 95 (I think 93-95) ZJ it's located behind the glove compartment where part of the glove compartment can be removed.

I think some ZJ's 96-98 ? the relay center is located behind the passenger side kick panel? I would need to verify. IIRC screws on the kit panel need to be removed to access the relay center.

kody24

Mine is a 94. I believe it is in the same place. Thanks for the diagram. I might tear into it this weekend and see if removing the relay will cure it without affecting anything else.

Muddz

If you can find the security module I found this post ____

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According to the people at jeep it can not be disabled. WRONG!!!! here are the steps that work.
First you must pull the plastic off the front of the dash on the passenger side.
Behind the glove box you will find a metal box shaped compartment.
Inside that box is your alarm. DO NOT DISCONNECT IT YET
The most important thing is the jeep must be running before you disconnect the alarm.
Start the jeep and look at the little box and you will find one screw that is holding the alarm box in place. remove the screw and disconnect the wires going to it.
At this point you can turn off the jeep.
The reason you must have the jeep running is the computer shows it has an alarm in place and if you disconnect it while the jeep is not running it will shut down the jeep thinking it has been stolen.
With the jeep running and you disconnect the alarm it will not be able to send the code to the computer showing an alarm is in place and the jeep alarm will not cause you any problems ever again..
If you have questions about this just let me know at charlesj@nexband.com
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To access the relay center open the glove compartment and remove three screws along the hinge which removes part of the bottom of the glove compartment. The security module is sort of hidden with less access on the left side.

kody24

Thanks. The logic there makes sense. I will have to put this off for at least a day though, just went for a drive and lost 4th gear. I just put the tranny in yesterday so it may just be a little low on fluid still or I may need to do more adjusting with the throttle control cable. After I figure that out I may dig into the dash.