Wj factory alarm will not go off.

Scott86MJ

Scott86MJ

Well-Known Member
Joined
May 3, 2006
Location
Dallas
99 grand cherokee laredo. Key fob quit working now when i unlock the door with the key the alarm sounds. I have unhooked the battery for a week and when i reconnected it the alarm sounds. How can I kill it without a key fob? Thanks Scott
 
I got it to go off. Problem is i cant unlock the door with the key because the alarm sounds. Anybody know if you should be able to disarm the alarm using the key?
 
It sounds like the door ajar switch which is integral to the door latch is no good. It's a very common issue on them. Also, look for broken wires in the door jamb harness. The signal wire to the BCM/theft module *could* be broken. Unlikely, but a free check.

To replace the latch, roll up the window all the way, remove the door panel, remove the three torx latch screws on the side of the door and remove latch. Installation is the opposite but remember to tighten the set screw on the latch (access hole on side of door near latch screws).
 
Is their any way to test the latch before buying one for 80 bucks? I reconnected the plug to the door panel and the alarm sounded again. I disconnect the battery and it goes off till I open the door. Key fob will not work still. Thanks
 
You need some way to read the data in the Body Control Module to see if the latch is indicating being open or closed. Did you inspect for broken wires in the door jamb harness?
 
Jody Treadway said:
You need some way to read the data in the Body Control Module to see if the latch is indicating being open or closed. Did you inspect for broken wires in the door jamb harness?
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Nothing was broken that I could see. I can check with ohm meter when I get home. Do you know where the next connector is located from the door module connector? Also what kind of scanner can read the BCM? I bet my Harbor Freight Scan tool cannot :(. I see the DRBIII scan tools referred to in the factory service manual are really expensive even used. Thanks for your help!
 
Sorry, but all that I know of that will read what you need is a DRBIII. But admittedly, a DRB is all I ever used. There may be higher quality Snap On type scanners that would read also. The DRB will allow you to see what caused the last alarm set. i.e.- driver's door opened, liftgate latch, etc.

I don't want to roll the dice with your money, but it's always the driver's door disarm/ajar switch that causes this on WJs. The RKE use let's the passenger door module tell the theft alarm that the door was allowed open via remote. With your disarm/ajar switch being failed, the theft module isn't seeing a valid reason from the door module(s) for the door being open and thusly setting off the alarm. Make sense?
 
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Jody Treadway said:
Sorry, but all that I know of that will read what you need is a DRBIII. But admittedly, a DRB is all I ever used. There may be higher quality Snap On type scanners that would read also. The DRB will allow you to see what caused the last alarm set. i.e.- driver's door opened, liftgate latch, etc.

I don't want to roll the dice with your money, but it's always the driver's door disarm/ajar switch that causes this on WJs. The RKE use let's the passenger door module tell the theft alarm that the door was allowed open via remote. With your disarm/ajar switch being failed, the theft module isn't seeing a valid reason from the door module(s) for the door being open and thusly setting off the alarm. Make sense?
Click to expand...
Yeah makes since i will order a new latch Monday. Thanks
 
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