I have a 2005 Lincoln LS V8 and the alarm system goes off randomly in the middle of the day, at night, basically whenever it wants to. The car starts and functions just fine and the alarm turns off after I hit unlock on the key fob like it should. The battery is new, the key fob battery is new, it doesn't seem to do it as much if not at all when I lock the car manually but it's inconvenient. Anyone else have this issue or know a fix maybe pulling a fuse if it has it's own?
2005 Lincoln LS V8 Alarm System
- Thread starter Ryan749
- Start date
joegr
Dedicated LVC Member
Locking the car manually doesn't arm the alarm, so it shouldn't do it at all when you do that. (Manually being flipping the inside lock lever by the door handle before closing the door, not using the key in the door.)
Do you ever get a false door ajar indication when driving? If so, it is probably caused by a faulty door ajar switch in the latch assembly of that door. The same goes far the trunk and trunk ajar warning. If it's neither of these, then the hood switch should be a suspect. Unplug it, and see if the problem stops. If it does, then you can adjust or replace the switch, or just leave it disconnected (if you do, then no alarm if someone does pry the hood open).
The perimeter alarm is integrated with other features. There's no fuse to disable it without disabling other stuff that you need.
Do you ever get a false door ajar indication when driving? If so, it is probably caused by a faulty door ajar switch in the latch assembly of that door. The same goes far the trunk and trunk ajar warning. If it's neither of these, then the hood switch should be a suspect. Unplug it, and see if the problem stops. If it does, then you can adjust or replace the switch, or just leave it disconnected (if you do, then no alarm if someone does pry the hood open).
The perimeter alarm is integrated with other features. There's no fuse to disable it without disabling other stuff that you need.
2005_LS_V8
Active LVC Member
I have the same persistent problem with my 2005 LS V8, still happening. I read on another thread where a poorly charged battery can cause this. I activated the hood plunger manually several times thinking that might be stuck, no change. I was about to replace that switch, but thanks Joe for the troubleshooting steps, will definitely be trying these ASAP.
While working through my stereo problems, which caused the Limp Mode to kick in, occasionally I had the 'door ajar' warning on the dash. I'd open and close all the doors and sometimes restart the car and it would go away.
One thing I have noticed over time is that, when I double click the lock switch on the key fob, that often precedes an alarm going off a couple of hours later. Definitely will try to manual lock switch inside the car to get my sanity back.
Hood switch has to be easy to replace, right, for a guy that doesn't like to get his hands too dirty on cars anymore like me? What about the door switches? Do I have to take off door panels to get to that?
While working through my stereo problems, which caused the Limp Mode to kick in, occasionally I had the 'door ajar' warning on the dash. I'd open and close all the doors and sometimes restart the car and it would go away.
One thing I have noticed over time is that, when I double click the lock switch on the key fob, that often precedes an alarm going off a couple of hours later. Definitely will try to manual lock switch inside the car to get my sanity back.
Hood switch has to be easy to replace, right, for a guy that doesn't like to get his hands too dirty on cars anymore like me? What about the door switches? Do I have to take off door panels to get to that?
joegr
Dedicated LVC Member
The hood and trunk switches are easy to replace.
The door switches are built into the door latch assemblies. The whole assembly has to be replaced. The bad news is that they are expensive new, but the good news is that they are no longer made and mostly out of stock. You are pretty much stuck with used on ebay or your local junkyard.
Oh, and they are difficult to remove.
The door switches are built into the door latch assemblies. The whole assembly has to be replaced. The bad news is that they are expensive new, but the good news is that they are no longer made and mostly out of stock. You are pretty much stuck with used on ebay or your local junkyard.
Oh, and they are difficult to remove.
nghtshd88
Well-Known LVC Member
Bought one on ebay that failed shortly after. Its the metal contact pin that gets warped after time. I doubt a used one at this point is worth it. Mine was stuck in the down position probably from the door never being opened. I just manually lock my doors now.
joegr
Dedicated LVC Member
Just to give a counter point to your anecdote... I replaced the rear latch assembly on my 04 with a used one from Ebay, about a year ago. So far, so good. (A metal part inside my original broke, so it would no longer unlock.)
2005_LS_V8
Active LVC Member
Is hitting the key fob lock button once the same as manually locking with the door switch? I know two key fob clicks arms it and I hear the chirp, curious about just a single click.
joegr
Dedicated LVC Member
No, and you are incorrect.
Hitting it once locks and arms it.
Hitting it twice chirps the horn so that you know you locked it. You can (via the message center, setup button) change it to chirp on the first press instead of requiring two. The PATS light flashing every now and then indicates that it is armed. This is in your owner's manual. (The alarm also arms if the press the lock switch on the inside of the door, or if you press the last two buttons of the keypad outside. Note that these don't chirp the horn either.
joegr
Dedicated LVC Member
Nope, no relays involved with this.
nghtshd88
Well-Known LVC Member
Just had this issue again.
However this time, I hit the lock button on the driver side panel as always then I unlocked the door manually and shut it (door unlocked) as I was running inside for something. Before I turned away I saw the PATS light blinking while the door was UNLOCKED. Opened the door and horn went off.. then it stopped about 15-30 seconds later as usual. I cant see these issues being anything related to door ajar now as I had the door unlocked to begin with. I dont even get those messages. I feel like the alarm has a mind of its own. Even if I hit the lock manually it should remain disarmed. No AF electronics and fairly new battery.
However this time, I hit the lock button on the driver side panel as always then I unlocked the door manually and shut it (door unlocked) as I was running inside for something. Before I turned away I saw the PATS light blinking while the door was UNLOCKED. Opened the door and horn went off.. then it stopped about 15-30 seconds later as usual. I cant see these issues being anything related to door ajar now as I had the door unlocked to begin with. I dont even get those messages. I feel like the alarm has a mind of its own. Even if I hit the lock manually it should remain disarmed. No AF electronics and fairly new battery.
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joegr
Dedicated LVC Member
If you "hit the lock button on the driver side panel" then you arm it (once the door is closed afterwards).
If you "unlocked the door manually" then you did not disarm it. There is no switch or sensor for it to be able to know that you manually unlocked the door from inside (there is such a switch for the key in the outside of the door). It thought the driver's door (and all the other doors) where still locked.
You are describing correct and expected behavior.
If you "unlocked the door manually" then you did not disarm it. There is no switch or sensor for it to be able to know that you manually unlocked the door from inside (there is such a switch for the key in the outside of the door). It thought the driver's door (and all the other doors) where still locked.
You are describing correct and expected behavior.
1LoudLS
Dedicated LVC Member
if you use any of the electronics or the key to lock the door, then the alarmed gets armed
if you use any of the electronics or the key to unlock the door, then the alarm is disarmed
if you use your hand on the lock lever to lock the door then the alarm does not get armed
if you use your hand on the lock lever to unlock the door then the alarm does not get disarmed.
if you use any of the electronics or the key to unlock the door, then the alarm is disarmed
if you use your hand on the lock lever to lock the door then the alarm does not get armed
if you use your hand on the lock lever to unlock the door then the alarm does not get disarmed.