The anti-theft alarm keeps coming on after the car has been parked and locked. How can I deactivate it. I have double checked evrything is properly closed and locked. It has been an intermittent fault in the past few weeks but appears permanent now and the car has to be left unlocked to avoid causing a nuisance to our neighbours. We cannot leave it unlocked in a public place under any circumstances.

Could be messy since disabling the alarm may disable your ignition circuits so you have to be really careful about this procedure. Sometimes they have kits to bypass the system and they guarantee that it will work - might want to look into that alternative.

Hi Carol , do you mean PATS passive antitheft system ? Locked up your car ,do you mean it won't crank over an start ?
The passive anti-theft system uses radio frequency identification technology to deter a driveaway theft. Passive means that it does not require any activity from the user.

• During each vehicle start sequence, the ignition key identification code is requested by the vehicle protection anti-theft electronics.
• If the key's ID code has been programmed into the system, the powertrain control module (PCM) (12A650) is signaled to enable the vehicle to start.
• If the key's ID code is not programmed into the system, or if no encoded key is detected, then the powertrain control module is signaled to disable the vehicle.

The passive anti-theft system communicates the state of the security system to the powertrain control module via the J-1850 communications network data link connector (DLC). The powertrain control modulebased on the communications from the passive anti-theft system, will determine if the vehicle's engine is enabled to start. The passive anti-theft system differs from the active anti-theft alarm system in that the passive anti-theft system enables/disables the vehicle from starting and only operates with the ignition switch in RUN/START position. The active anti-theft alarm system has perimeter protection capabilities and operates only with the ignition switch OFF. Refer to Section 13-11A for active anti-theft alarm system information.
Vehicle Disabling The passive anti-theft system will be activated and disable the vehicle from starting if any of the following conditions exist:

• damaged encoded key
• unprogrammed key
• non-encoded key (key has no electronics)
• wiring concern
• transceiver concern
• Passive Anti-Theft System (PATS) control module concern
• J-1850 Communications Network concern
• Powertrain Control Module (PCM)

Instructions

1. • 1 Ensure that the doors, hood, decklid and rear liftgate are properly closed. The alarm cannot properly arm if any of the doors or other openings are not closed.
     
   • 2 Replace the batteries in the key fob to ensure that the remote is capable of arming the alarm system. If the batteries have been dead for more than a few minutes, the fob will need to be synchronized with the vehicle to function. To synchronize the remote with the car, aim the remote at the vehicle and press the lock or unlock button twice. Next, place the key in the vehicle's ignition and turn the ignition switch to the "On" position. All of the steps must be completed within 30 seconds.
     
   • 
     
   • 3 Verify that the parking lamps flash three times when the system is armed using the remote. Alternatively, verify that the alarm is armed by looking at the alarm indicator on the dash. If the alarm is properly armed, the alarm indicator light should blink.
     

Could be the module is fubar since you have B+ at the terminal. U can also install a hidden double pole switch that deactivates the fuel pump and ignition circuits. And if you want to be fancy you can do the same with a relay that opens those circuits automatically when ignition key is removed so you do not even have to throw a switch!

Check the help links mentioned below :---Relearn Theft deterrent module? http://technoanswers.blogspot.com/2012/01/relearn-theft-deterrent-module.html
---------theft deterrent module Relearning? http://howtobyme.blogspot.com/2012/01/buick-theft-deterrent-module-relearning.html
--------Engine will not crank after relearning Theft deterrent module? http://howtobyme.blogspot.com/2012/01/engine-will-not-crank-after-relearning.html
--------Can car radio code block Passkey anti theft system ?

http://schematicsdiagram.blogspot.com/2011/12/can-car-radio-code-block-passkey-anti.html
Car Factory Alarm will go off? http://repairhelpcenter.blogspot.com/2012/01/toyota-avalon-factory-alarm-will-go-off.html
---------Car will not start security lock out? http://technoanswers.blogspot.com/2011/12/car-will-not-start-security-lock-out.html
---------Alarm will not disengage? http://technoanswers.blogspot.com/2012/01/ford-pickup-alarm-will-not-disengage.html
--------This will help.For more info keep updated.Thanks.

Take it back to dealer for quandry. I wouldn't fool with it if evrything else works.

On internet there is a manule, disarm the Anti-Theft system. Check door and trunk switches re-engage system.

The ignition lock anti-theft switch (19A438) detects if the ignition key cylinder is broken or "slam pulled" during a theft. The ignition lock anti-theft switch is always monitored by the remote anti-theft personality (RAP) module. This allows the alarm system to be triggered in the case that the ignition lock anti-theft switch detects tampering of the ignition key cylinder (even in the event that the alarm is not active at the time).
Refer to the Section 501-14B for more details on the keyless entry remote transmitter (15K601).
The door open warning lamp switch (14018) communicates to the RAP module through the generic electronic module (GEM). This input to the RAP will cause the anti-theft alarm to be sounded if the anti-theft alarm was armed.
The door disarm switches are assembled into both LH and RH lock sets. The door disarm switch must be triggered before the mechanical lock unlocks. This is to prevent the anti-theft alarm from activating when it should have been disarmed.
The RAP module controls the anti-theft system and is the brains of the keyless entry system. The RAP module communicates with the GEM to request that the interior lights be turned ON/OFF with use of the keyless entry remote transmitter, and the GEM communicates to the RAP to inform when the door is opened. Refer to Section 418-00 for inter-module communication.
The RAP module has three wire connectors attached to it:

• The antenna for the keyless entry remote transmitter.
• 26 circuit connector (C256).
• 22 circuit connector (C257).

In addition to the perimeter alarm that uses the door open warning lamp switch, the RAP module also uses the ignition lock anti-theft switch and the autolock/relock feature to prevent theft of the vehicle. For a full description of the autolock/relock system, refer to Section 501-14B .
The THEFT LED is found on the instrument panel between the tachometer scale and the needle pivot point. The LED is illuminated during prearming and flashes when armed or triggered.
Prearming and Arming the System
The system can be armed if:

• The ignition is OFF.
• The PANIC alarm is OFF.
• All doors are closed.

There are two ways to prearm the system:

• Press the LOCK button on the transmitter.
• Open a door, press the power door lock button and close the door.

After 30 seconds the system will be armed and the theft indicator in the cluster will flash every two seconds.
Disarming an Untriggered System
An armed system will be disarmed with one of these valid actions:

1. Pressing the UNLOCK button on the transmitter.

1. Placing a key in the door and turning to UNLOCK.

1. Turning the key to RUN or ACC.

The anti-theft alarm can be triggered by the following conditions:

• The ignition cylinder is damaged with or without the RAP being armed.
• A door is opened without disarming the armed RAP module.

The remote transmitter can activate a panic alarm which is similar to an anti-theft alarm, but does not deactivate the starter or cause the theft indicator to flash.
Disarming a Triggered System
If the system has been triggered, (the horn honks, the lights flash, and an external starter interrupt relay is engaged), the system can be disarmed by:

1. Pressing the UNLOCK or PANIC button on the transmitter.

1. Putting a key in the door and unlocking the door.

1. Turning the ignition to RUN/ACC (Turning the key to RUN/ACC will not disarm an alarm that has been triggered by the ignition lock anti-theft switch.).

Section 13-11: Anti-Theft System, Active 1998 Windstar Workshop Manual DESCRIPTION AND OPERATION Anti-Theft Alarm System NOTE: The system immediately monitors the ignition key lock cylinder upon removal of the key from the ignition. It is not necessary to arm the system for ignition key lock monitoring.

The anti-theft alarm system:

• protects the vehicle from unauthorized entry into the passenger compartment, engine compartment and cargo area.
• monitors the status of the ignition key lock cylinder.
• is controlled by a remote anti-theft personality (RAP) module. The remote anti-theft personality module also controls the electronic door lock functions. Refer to Section 01-14B for more details.
• when armed, detects unauthorized entry into the passenger compartment by using an input from the GEM module regarding the state of the door or liftgate (open or closed).
• protects the engine compartment with a hood switch which is located on the LH cowl vent panel and is part of windshield wiper motor wiring (17A477) .
• triggers an alarm if the ignition lock cylinder is forcibly removed from the steering column.

Once triggered, the system responds by:

• flashing the low beam headlamps, the parklamps, rear lamps and the alarm indicator warning light emitting diode (LED).
• sounding the horn (13832).
• disabling the starter circuit until the system is disarmed.

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Remote Anti-Theft Personality Module

• The remote anti-theft personality module is located behind the instrument panel (04320).
• It contains a radio receiver that receives the RF signal from the keyless entry remote transmitter (15K601) through the alarm and lock system antenna (15603) and sends the appropriate command to the power door locks, the horn relay, or the generic electronic module.
• The remote anti-theft personality module is equipped with an internal backup power supply which holds the programmed code in memory in the event the vehicle battery is disconnected.

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Remote Anti-Theft Personality Module Removal

1. Disconnect battery ground cable (14301). Refer to Section 14-01 .
   

1. Remove radio. Refer to Section 15-01 .
   

1. Remove lower instrument panel center finish panel. Refer to Section 01-12 .
   

1. Lower glove box.
   

1. Remove two remote anti-theft personality module bracket retaining screws.
   

1. Disconnect electrical connectors and alarm and lock system antenna (15603).
   

1. Remove remote anti-theft personality module and bracket.
   

1. Remove remote anti-theft personality module from mounting bracket.
   

Installation

1. To install, follow removal procedure in reverse order.
   

1. Tighten remote anti-theft personality module bracket retaining screws to 6-8 Nm (54-70 lb-in).
   
   

Components The system is composed of the following components:

• remote anti-theft personality (RAP) module with integral antenna
• alarm indicator LED
• door lock cylinder switch RH, door lock cylinder switch LH
• liftgate door lock cylinder switch (220A40)
• hood switch (part of windshield wiper motor wiring (17A477))
• ignition lock anti-theft switch (19A438)

The following vehicle components are also used by the anti-theft alarm system:

• generic electronic module
• power door lock switch (14028)
• door open warning lamp switch (14018)
• autolamp relay (14N089)
• horn relay and bracket (13853) and horn (13832)
• low beam headlamps
• rear lamps (13404) and parking lamps (13200)
• starter relay
• door lock relays
• keyless entry remote transmitter (15K601)

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Disarming an Untriggered System NOTE: A perimeter alarm will "shut off" after 165 seconds, but the system is still triggered and is not disarmed.

An armed but untriggered perimeter anti-theft system can be disarmed by one of the following four events:

1. Unlock the doors by pressing the keyless entry remote transmitter (15K601) UNLOCK button once.
2. Unlock any door with a key.
3. Turn ignition switch to RUN or ACC.
4. The remote entry PANIC button will disarm the anti-theft system only when the perimeter alarm is triggered and sounding.

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System Triggering NOTE: Although the remote entry PANIC alarm is not associated with the monitoring of the vehicle, the user will frequently say that the theft system was triggered when actually the keyless entry remote transmitter PANIC button was inadvertently pressed. A panic alarm will not flash the THEFT indicator.

The alarm can be triggered by the following events if the system has been armed and has not been disarmed first:

• Open any door or liftgate.
• Open the hood (16612) (if the hood was open when the system was armed, it must be closed before it can trigger the alarm).
• Dislodge the ignition key lock cylinder.
• The anti-theft system may be triggered inadvertently when the module is disconnected and then reconnected. To avoid inadvertent alarm triggering, disconnect the smaller 22-way connector first.

When the system is triggered the perimeter alarm will operate as follows: The remote anti-theft personality module will pulse the following outputs at approximately 1.3 Hz, 50 percent duty cycle for two minutes 45 seconds for North America. NOTE: Other perimeter alarms can be programmed for the system.

• low beam headlamps
• parking lamps
• horn
• THEFT indicator

The perimeter alarm can be retriggered, after a perimeter alarm has sounded for 165 seconds. After a perimeter alarm has timed out, if any trigger input is first seen as normal and is then seen in its trigger state, the perimeter alarm will be retriggered. The perimeter alarm can be triggered a total of three times between an arming sequence and a disarm event. An active panic alarm will be deactivated when a perimeter alarm is triggered (a perimeter alarm overrides a panic alarm).

i put a new stereo in my 1998 isuzu trooper now the anti theft wont let car start what do i do