Anti-theft and engine immobilization system — general information (Opel Astra G)

Layout diagram of anti-theft system elements

See also the information provided in Chapter User manual.

General information

All models are equipped with an immobilization device that effectively prevents unauthorized attempts to start the engine. The system is activated by the ignition key and an electronic sensor built into the ignition switch.

The control unit of the anti-theft system uses contact and volume sensors to monitor the condition of all doors, including the tailgate/ tailgate, hood and ignition switch, as well as the volume of the interior and luggage compartment and the roll of the car (see illustration Layout diagram of anti-theft system elements). The control unit is installed at the bottom of the right front pillar near the passenger's feet and is covered by a decorative panel. Ultrasonic (volumetric) sensors are installed in the upper part of the central pillars and react to any changes in the interior volume. Tilt sensors react to changes in the car's roll even when attempting to remove a wheel. The main alarm siren of the anti-theft system is installed on the left on the engine compartment bulkhead under the hood, an additional siren is installed under the left front wing. On the Station Wagon and Zafira models, the glass condition sensor is installed in the luggage compartment, closer to the rear side window.

Removal

Before removing any anti-theft system component, the negative battery cable must be disconnected.

Engine/Transponder Immobilizer Unit

1. Remove the steering wheel and steering column cover (see Chapter Suspension and steering). On models equipped with a latch block, remove the lock cylinder (see Removal and installation switches), then remove the unit from the lock housing and disconnect the wiring. On models with a unit without latches, disconnect the wiring, then remove the unit from the ignition lock housing.

When installing a new unit, it must be programmed using special equipment in a car service workshop.

Hood contact sensor

1. Remove the two mounting screws, remove the sensor and disconnect the electrical wiring from it.

Main siren

1. To remove the emitter, remove the water-deflecting plate from the engine compartment bulkhead, loosen the mounting nut and disconnect the electrical wiring.

Additional siren

1. Remove the left front wheel arch protection liner (see Chapter Body), disconnect the electrical wiring, unscrew the mounting bolts and remove the siren from the wing splash guard together with the support bracket.

Door contact sensor

Cm. Removal and installation switches.

Components of a single lock

See Chapter Body.

Anti-theft system and single lock control unit

1. Loosen the mounting screw and remove the lower decorative panel of the right front pillar, then remove the side trim panel of the footwell. Disconnect the electrical wiring, loosen the two mounting nuts and remove the control unit.

Remote control power supply

For a description of the procedure for replacing the remote control battery, see Chapter User manual.

Installation

Installation of all components is carried out in the reverse order of their dismantling. Any faults in the system must be repaired at a service station.