Alarm Problem - 2003 LS

[LS-jsf]

The car alarm goes off on occasion when it shouldn't. I have been standing by it and no one was near or touching the car. I've went through and read many of the posts (search) on car alarm problems, but I want to run my issue by here as I'm not sure I found the answer in the other posts. What I did learn from them was: alarm only works if someone tries to open the doors, hood or trunk. It doesn't go on if someone pops out a window or a loud vehicle goes by, etc. A bad door, trunk or hood switch can cause it to go off, but is that only if you're getting like a 'door ajar' message when the door is not ajar?

Here's my problem. It goes off randomly, if the car is in the garage, the doors are not locked of course, so no alarm is activated, never an issue. But when we're out somewhere and parked or out of town and not parked in a garage, car is locked and sometimes the alarm will go off. I've even been standing near it and it has gone off and no one is near the car.

I never get any messages like the door is ajar if it's not.

The battery works fine and no other issues that would indicate a weak battery.

If the hood or trunk switch is bad, how do you figure that out, is there a way to test it, or do you just have to replace it and see if that solves the problem? How hard are they to install should I end up having to go that route?

And I'm confused from some of the posts. Are you able to lock the car without activating the alarm? I read where someone says if you use the remote FOB and click the lock button once, it doesn't activate the alarm, click it twice and it does. What is the reality about once or twice, I was under the impression doing either one turns on the alarm? Thanks for your help.

 

[joegr]

If it's the hood switch, you get no "ajar" message, so maybe start there. A quick and dirty test is to unplug the hood switch and see if the false alarms go away.

AFAIK, any locking with the remote will arm the alarm. Someone may have confused the no chirp on one press and a chirp on two presses with the alarm function. You can manually lock the doors and the alarm is not armed.

 

[LS-jsf]

Thanks Joe. At least we can turn off the alarm when needed until we can figure out how to correct the problem. Where is the location that the hood switch unplugs?

 

[joegr]

... Where is the location that the hood switch unplugs?

Right at the hood switch itself.

 

[LS-jsf]

Oh when you mentioned 'dirty' test, I thought maybe it was at the end someplace by the firewall or something. Thank you for the help Joe.

 

[RigsLS]

... You can manually lock the doors and the alarm is not armed.

Huh?

SECTION 419-01A: Anti-Theft — Perimeter

The alarm can be armed using:

• The LOCK button in the remote keyless entry (RKE) transmitter to the DDM, which sends a message through the standard corporate protocol (SCP) communications network to the FEM.
• the driver or passenger door lock switch if the corresponding door is open when LOCK is actuated.
• the key in the driver door lock cylinder.
• the RKE keypad by pressing 7/8 and 9/0 simultaneously.

further:

• Monitor the DDM PIDs D_DSRM and DRLKCYL while turning the key in the driver door lock cylinder to the LOCK and UNLOCK positions.
• Do the DDM PID values agree with the LOCK positions?

more: DIAGNOSIS AND TESTING
.

 

[LS-jsf]

I did what Joe suggested and the red blinking alarm light on the dash does not light/blink when manually locking the doors. So I'm assuming the alarm is not on if that light is not, correct?

 

[RigsLS]

Perhaps the Workshop and the Owner manuals are wrong I guess. Says clearly it's supposed to arm it.



2004 LS Owners Manual
http://www.lincolnvscadillac.com/tech/Lincoln-LS/2004LincolnLS-OwnersManual.pdf

Page 152/320

Arming the system
When armed, this system will respond if unauthorized entry is
attempted. When unauthorized entry occurs, the system will flash the
turn signal lamps and will sound the horn.
The system is ready to arm whenever key is removed from the ignition.
Any of the following actions will prearm the alarm system:

Press the control on the remote entry transmitter.
Press the driver or passenger interior power door lock control while that respective door is open, then close the door.
Lock the vehicle with the key in the driver’s door key cylinder.
Lock the vehicle by pressing the 7-8 and the 9-0 on the keypad at the same time (with the driver’s door closed).


Theft indicator
When the vehicle is locked using one of the listed methods, the theft indicator located on the instrument panel will flash briefly every 2 seconds to indicate that the perimeter alarm system is armed.


.

 

[RigsLS]

Just read this unrelated information. Which I always understood as having to go to the Dealership to obtain it.

The keypad can be operated with the factory set 5–digit entry code; this code is located on the owner’s wallet card in the glove box, is marked on the computer module, and is available from your authorized dealer. You can also create your own 5–digit personal entry code.

 

[RigsLS]

I did what Joe suggested and the red blinking alarm light on the dash does not light/blink when manually locking the doors. So I'm assuming the alarm is not on if that light is not, correct?

Just went out to my 04 LSE and when I turn the key to the right on the drivers side door, it locks all doors and the PAT light begins to flash. System is armed.

Don't know what to tell ya.

perhaps have a look at DIAGNOSIS AND TESTING and see what works or doesn't for you.
Look for something related to the DDM. Unless you and Joe have different options then I do, it's supposed to arm the system when the drivers door lock is turned to the LOCK position. Only difference I can think of is the fact I own the "For Canadian Market" LS'es but I doubt that would have anything to do with it.<shrugs>

Not trying to pester you folks but it is what it is. The system appears to arm itself when locked drivers side manually using the supplied programmed keys. <double-shrugs>


GLWR


.

 

[joegr]

RigsLS, I didn't say to lock the doors with the key. I said to manually lock them. When you get out of the car, with your door still open, reach over and flip the manual lock lever (just above the interior door handle) to the locked position. Now close the door. The car doesn't even know the door (I assume in this example that the remaining doors were never unlocked) is locked now.

Locking with the key is not locking manually. The key still triggers a switch.

 

[LS-jsf]

This is what I did as Joe suggested and it appears to lock the car without the alarm on. Manually push the chrome lock(s) on the door(s), shut the door(s) and the car is locked and the red alarm light on the dash does not turn on/blink. At least it did work for me that way.

RigsLS, I didn't say to lock the doors with the key. I said to manually lock them. When you get out of the car, with your door still open, reach over and flip the manual lock lever (just above the interior door handle) to the locked position. Now close the door. The car doesn't even know the door (I assume in this example that the remaining doors were never unlocked) is locked now.

Locking with the key is not locking manually. The key still triggers a switch.

 

[RigsLS]

Splendid !!! we're on the same page now. Trying to lock the car but not set the alarm on purpose 10-4 !!!

How about troubleshooting the fault and fixing the alarm?

 

[joegr]

I assumed that he was just wanting to do this until he has the problem resolved. Meanwhile, he's probably not wanting the battery to keep getting run down...

 

[LS-jsf]

Yes we're out of town at the moment, just wanted to fix the alarm going off right now, but I do want to fix the problem when I get back home. I'll check out the hood switch when I return.

I assumed that he was just wanting to do this until he has the problem resolved. Meanwhile, he's probably not wanting the battery to keep getting run down...