PATS/Security Issue

[nghtshd88]

This has happened a couple times already. The red light will start blinking with 1 second pauses out of no where as if the car is armed. Today the car was sitting unlocked for a day, I opened the trunk manually then doors and it went off. Before I would just hit the unlock button on the fob but now that doesnt unarm it.. I disconnected the battery for a bout 5-10mins and it did nothing except this time the button on the fob was able to unarm it afterwards. It seems to only when the temperature spikes.

Wasn't sure if key in the ignition would unarm it and didnt try the drivers door lock. Randomly my trip odometer will reset itself also. Besides some bad wiring im assuming this couls be pcm, bcm, guage cluster? Not sure or where to start..

 

[joegr]

Since it seems like this involves more than one module, I would look at the wiring first. I'd also check the condition of the battery. I have noticed that if you disconnect power and then reapply it, the perimeter alarm arms itself. I think that this is an intentional failsafe.

 

[AmsterDutch]

check the condition of the battery. I have noticed that if you disconnect power and then reapply it, the perimeter alarm arms itself. I think that this is an intentional failsafe.

Yes...yes...and absolutely yes...

It seems to only when the temperature spikes.

Might be worth breaking out the Multi-meter and checking voltage...also check the alternator

 

[04_Sport_LS]

Yup. OEM, (Motorcraft), batteries last about 7 years. Aftermarket batteries usually about 5.

 

[nghtshd88]

Still chasing this 4 years later.. I manually lock the drivers door shut it and the security light will blink as if I used the lock button to lock and arm it and then.. the alarm goes blaring off whenever it wants to and stops itself after a couple seconds to go back to as if it was armed and nothing tripped it.

If I hit unlock on the fob it wont disarm which is what I dont understand. I have to hit lock on the fob to arm it then unlock to get the light to stop flashing.

It might be coincidence but yesterday I had left an accessory on and it drained the battery to the point of no crank and reset the cluster. Within a couple hours it had enough to crank and drive away. Put about 3hrs of driving on it since seems to be fine. Connections are perfect on battery. This is the first "cool" night in a long time. Its basically done this since the battery was new anyway..

Ive used forscan and it tells me absolutely nothing code wise.. does the DDM control PATS or the cluster?

I feel like like getting a motorcraft battery even though this autocraft gold is fine just because this car likes nothing aftermarket.. I had this one tested a few months ago and it came out fine.

 

[joegr]

...

Ive used forscan and it tells me absolutely nothing code wise.. does the DDM control PATS or the cluster?

...

I think you are confusing the perimeter alarm with PATS. The two are not related, other than that they both use the same warning light in the autolamp/climate control sensor assembly.
PATS runs from the cluster micro. The perimeter alarm runs from the DDM, FEM, and REM, AFAIK.