Theft Warning System

From Z32 Wiki
Jump to: navigation, search
The stock theft warning system, when armed, monitors the doors, hood, locks, and hatch (trunk in convertible, along with radio bezel in convertible), and when any of these are disturbed, sounds the theft warning horn, flashes the headlight high beams, and disables the starter. The 'SECURITY' lamp on the instrument cluster indicates the system state. It can be armed by locking the doors, manually or with the key, but can only be disarmed by unlocking one of the doors or hatch with the key.

The 32x32px has a section on the theft warning system, available here: (93 USDM). Other model years may have different wire colors and harness connections.

Component locations and descriptions

Theft_warning_system_-_Component_layout.png

Note: 'Pin X' refers to the pin as labeled on the control unit connector, unless otherwise stated.

A. Theft warning relay


Location: Engine bay fuse/relay box
Function: Disables starter by interrupting the starter relay coil

Theft_warning_system_-_Warning_relay.png



B. Hood switch


Location: Engine bay, in front of driver's side upper shock mount
Function: Triggers alarm when hood is opened by grounding pin 15.

Theft_warning_system_-_Hood_switch_2.png

Theft_warning_system_-_Hood_switch.png



C. Theft warning control unit and horn relay


Location: Passenger side footwell, attached to lower dash support,
above the ECU.
Function: Processes system inputs and triggers outputs. Horn relay
is activated when alarm is triggered by grounding pin 12.

Theft_warning_system_-_Control_unit_pinout.png

Theft_warning_system_-_Control_unit_and_horn_relay.png



D. Door lock switch, unlock switch, key cylinder tamper switch


Location: Driver and passenger door handles
Function: Door lock / unlock switch - When key is used to lock the door,
pin 7 is grounded. When key is used to unlock the door, pin 11 is
grounded. Arms / disarms the system.
Door key cylinder tamper switch - If the key cylinder is removed
from the door, pin 5 is grounded.

Theft_warning_system_-_Door_lock_switch.png



E. Door switch


Location: Driver and passenger door jambs
Function: Triggers alarm when door is opened by grounding pin 6.

Theft_warning_system_-_Door_switch_2.png

Theft_warning_system_-_Door_switch.png



F. Door unlock sensor


Location: Driver and passenger door, inside, below latch
Function: Tells the control unit if the door is unlocked, so it can know if a
door was locked or unlocked manually (without a key).

Theft_warning_system_-_Door_unlock_sensor.png



G. Back door switch, unlock switch, key cylinder tamper switch


Location: In rear, behind center trim panel (except convertible)
Function: Door switch - Triggers alarm when hatch is opened by grounding
pin 6 and 14.
Unlock switch - When the hatch is unlocked with a key, pin 10 is
grounded.
Door key cylinder tamper switch - If the key cylinder is removed
from the hatch, pin 5 is grounded.

Theft_warning_system_-_Back_door_switch.png



H. Theft warning horn


Location: Engine bay, underneath battery tray.
Function: Horn is sounded when alarm is triggered.

Theft_warning_system_-_Warning_horn.png

Normal operation


To check if the stock alarm is operating correctly, make sure the doors, hood, and hatch are all closed. The SECURITY light on the instrument cluster should not be illuminated. Open each door individually, and confirm the SECURITY light flashes when the door is open and goes out again when the door is closed. Repeat for the hood and hatch. Now, with all doors, hood, and hatch closed, and the driver's window open, lock the driver's door, and confirm the SECURITY light goes solid for 30-40 seconds, then goes out. The system is now armed. Reach inside the open window and unlock and open the driver's door. The alarm should be triggered, sounding the horn and flashing the lights. Get in the car and attempt to start it with the key. The starter should not work. Disarm the alarm by unlocking the driver's door with the key. The horn and lights should stop flashing, and the car should now start with the key.

Troubleshooting

The SECURITY light is always flashing

This means the control unit sees one of your doors, hood, or hatch as open. Not only will this prevent the system from arming, but it also places a drain on the battery when the car is parked. A common culprit is the hood switch, as the bracket that holds it in position can be bent downward, causing the hood not to make contact when closed. A fault with the other door switches, hatch switch, key cylinder tamper switches, or harness are also possible. Use Diagnostic Procedure 1 in the FSM extract at the top of the page if the problem is not readily apparent.

The alarm goes off and my key won't disable it

Often this is because the plastic piece connected to the key cylinder in the door breaks off, which means the door unlock switch is never triggered when the door is unlocked with the key, so the control unit never sees the door unlock signal. This can be checked by removing the door panel and looking at the back of the key cylinder. Z1 Motorsports sells a metal replacement which can be seen here. If this is not the problem, use Diagnostic Procedure 7.

Theft_warning_system_-_Door_trigger_missing.jpg
Door lock cylinder missing unlock trigger piece


Integration with aftermarket alarm

The stock theft warning system can be retained with an aftermarket alarm, and its wiring harness provides several useful connections to tap into at the control unit. All door switches, key cylinder tamper switches, and lock / unlock sensors act as open circuits when normal (door / hatch / hood closed, key cylinder intact) and connect to ground when activated (door / hatch / hood open, key cylinder removed, door lock / unlock signal). To arm the stock system with the aftermarket alarm, tie the door lock switch, pin 7, to a grounded output when the doors are locked with the remote, and tie the door unlock switch, pin 11, to a grounded output when the doors are unlocked with the remote. If desired, the stock theft warning system can be disabled by simply disconnecting the control unit. This has no effect on any other vehicle systems.