Question about 2002 Mercury Mountaineer

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The door ajar sensor keeps going into alarm and triggering the security system. I can not find any sensors on any door jam that would be causing this problem. Is there a circut board or some other fuse that might be causing this?

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  • flight5303 Jul 09, 2010

    Thank you so much for the quick response! That is exactly what mine is doing> that should do the trick



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Get a can of WD 40 and put the little red tube that's taped on the side of the can onto the spray button at the top of the can, then open each door and spray the WD 40 into the door latch mechanism on the edge of each door. If you can't find the mechanism, open the door about 8" from the closed position, and look at the edge of the door. The mechanism is inside the horizontal **** that's about 1/2" wide and about 3" long, there's also 2 fastners above the opening and one below. Try to get the red tube into the edge of the opening and remember to spray both up, down and all around in there. If it doesn't work the first time, do it again, and remember to open and close the door numerous times after spraying to distribute the lube. Also remember that the courtesy and mirror lights are on a delay anyway, so it'll take a minute for them to go off, even when the probelm is fixed. But the door ajar display will disappear.... I had the same problem with my '02. WD40 worked for 2 days then, alarm at 2:30 AM the truck thinks the door just opened. I fixed problem permanently by changing the door ajar sensor located at the bottom of the door lock inside the door panel. You can barely see it, it is a light pink color and you have to get the tape off of it to unclip the plug. you have to twist the plug to get it out, on the driver door I twisted to the right. The part cost me $33.75 from a local guy, the dealer had one in stock for $33.25 but I like to support the small business. I had to take out the whole door lock assembly to get enough room to twist the old one out, do this by taking out 3 torx screws with a size T27 bit and unclip the door lock arms with the yellow clips on the lock assembly, then slide it up and around the window channel. I believe it may be possible to do this without taking out the lock, but this is how I did it. I knew it was the driver door because I would open it and the truck would not know it was open, so I avoided the $70 the shop wanted for diagnosis. now I can lock my truck at night with no fear of false alarms and no more annoying beeps as I try to drive down the street and not get road rage.

Let me know,if needed further assistance.

Hope i helped you.

Thanks for using ' Fixya ' and have a nice day!!

Posted on Jul 09, 2010


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