2001 Pathfinder Door Lock Sensor???

[cps2001path]

I have read through most of the threads talking about alarms going off intermittently. Unfortunately, my problem is a little different. When I close the doors and lock them (with the key externally or with the switch internally) and then unlock the door, the alarm goes off. It started off doing it intermittently. Then it started going off every time I unlocked the doors. I finally pulled the fuse for the circuit. Unfortunately, that same fuse controls the keyless entry, the horn, and all steering wheel controls (cruise, stereo). So I need to determine what the real problem is to gain back the other functionality.

Any ideas?

TIA

[Pwnin O'Brien]

So you're saying when you lock the doors manually by pressing the interior lock switch or if you lock the doors using the key in the driver/passenger door cylinder it arms the factory alarm system? Do you know if there might be an aftermarket alarm on the vehicle? The factory alarm system doesn't arm unless you use the keyless remote, so it's shouldn't be going off when you open the doors. If there is no aftermarket alarm on the vehicle and it is the factory alarm going off, then it sounds almost like the alarm is staying armed permanently and never disarming.

[cps2001path]

To my knowledge there is no aftermarket alarm. I'm not 100% certain of the locking sequence. I thought it was doing it when I locked it with the key and/or the keyless remote. I will re-install the fuse to test that.

A year or so ago a tech at the local dealer told me it might be the door lock sensor which equated to approximately $500.00 to repair without elaborating . So I have lived with it until now.

[Pwnin O'Brien]

Well, there is no door lock sensor on your vehicle, there are door sensors which would only be $30 and take about two minutes to replace. However, your door sensors are not the cause of your problem. What the mechanic may have been talking about is the SECU which controls your door locks, keyless entry, factory alarm, interior lighting, etc. This unit can be very expensive to replace at a dealer, but a forum member just replaced their SECU for less than $100 by purchasing from an auto recycler.

Try these tests first...

1. Unlock the vehicle with the keyless entry remote (even if the doors are already unlocked). Now open/close all five doors. Now lock all five doors using the interior lock switch. Check all five doors to ensure they are locked. Now unlock the vehicle using the drivers door key cylinder. Does the alarm go off?

2. Unlock the vehicle with the keyless entry remote (even if the doors are already unlocked). Now open/close all five doors. Now lock all five doors using the drivers door key cylinder. Check all five doors to ensure they are locked. Now unlock the vehicle using the drivers door key cylinder. Does the alarm go off?

3. Unlock the vehicle with the keyless entry remote (even if the doors are already unlocked). Now open/close all five doors. Now lock all five doors using the keyless entry remote. Check all five doors to ensure they are locked. Now unlock the vehicle using the keyless entry remote. Does the alarm go off?

Post the results of each tests

[cps2001path]

Turns out it was completely unrelated to locking or unlocking the doors. I replaced the fuse opened the driver and/or passenger door and the alarm engaged. I replaced the battery in the keyless remote and the problem went away after locking and unlocking the doors using the keyless remote. Apparently, the system was stuck in the last known state (armed) when the keyless remote died. So no matter what I did, opening the doors engaged the alarm.

Seems like opening the door with the key would disengage the alarm with or without the keyless remote. Is there a sensor in the key tumbler that might be bad?

[Natedogg1701]

if you lock the truk with the lock button inside or use the key and lock it the factory alarm does lock. if you watch the security light stays on solid for 30 seconds then blinks intermittently. because i had that problem of the factory alarm going off intermittently for no reason, so inseatd of using the key fob i just hit the inside lock switch or used the key in the driver door, and that still armed the system. only way i cud lock it w/out arming the system was to lock the truk wit the button inside or wit the key fob, unlock the driver door, and push the little lick handle to the locked possision by hand. that was a pain in the a** turned out i have a bad hood pin switch so i just disconnected it.