Operation CHARM: Car repair manuals for everyone.

Anti-Theft Alarm and Central Door Locking (CDL)



Description
The anti-theft alarm system is controlled by the Central Control Unit (CCU), which is mounted on the rear of the passenger compartment fuse box. The alarm can be armed and disarmed using the vehicle key or remote handset.

The two main features of the alarm system are:
- Perimetric protection.
- Volumetric protection.

Perimetric Protection
Perimetric protection secures against intrusion through the bonnet, doors, tail door or roof. The CCU monitors the state of the hinged panels after the alarm system has been armed. If a panel is opened after the alarm has been armed, the alarm will be triggered.

Switches are incorporated into the door latch assemblies, the bonnet, and the tail door. Three door vehicles also have a 'roof on' switch, to inform the CCU if the hard back has been removed, or the soft back is opened.

Perimetric protection is initiated after a valid alarm request is received. If any panel is open when perimetric protection is activated (other than the roof), the alarm will enter a partially armed state.

Volumetric Protection
Volumetric protection provides protection for the vehicle interior. A volumetric sensor monitors the vehicle interior space and activates the alarm if unauthorised movement is detected. The volumetric sensor is located in a central position, behind the headlining.

A fifteen second delay is initiated after the alarm has been armed before signals from the volumetric sensor are interpreted as an intrusion. This precaution is included in the CCU software to avoid accidental or nuisance triggering of the alarm.

Operation
Feed from the positive battery terminal (C0192) is supplied to the horn relay, fuse 6, fuse 7, fuse 10, and fusible link 4 (C0632) on an R wire. All are located in the engine compartment fuse box. Fuse 10 (C0575) provides a constant battery feed to the inertia switch (C0123) on a G wire. Fuse 7 (C0576) provides a constant battery feed to the hazard warning relay located in the passenger compartment fuse box (C0580) on an NO wire.

Fusible link 4 (C0574) provides a constant battery feed to the CCU (C0593), fuse 14, and fuse 15 of the passenger compartment fuse box (C0581) on an NW wire. Fuse 15 provides a feed to the CCU (C0593). Fuse 14 (C0589) provides a feed to the alarm LED located in the instrument pack (C0230) and the transponder coil mounted around the ignition barrel (C0049) on P wires. Fuse 14 (C0580) also provides a feed to the diagnostic socket (C0040) and the roof on switch (3 door vehicles only) (C0497) on P wires.

Door Switches
In order for the perimetric alarm system to operate, the CCU monitors the condition of the door switches (including the tail door switch). The door switches are open circuit when the doors are closed. When the doors are opened, the switches close and an earth path is created.

The CCU (C0428) is connected to the door switches as follows:
- To the driver door switch (C0441) on a PS then PW wire.
- To the passenger door switch (C0441) on a PW wire.
- To the LH rear door switch (C0442) on a PW wire.
- To the RH rear door switch (C0442) on a PW wire.
- To the tail door switch (C0616) on a BO wire.

NOTE: Both front and both rear door switches have the same connector number as they utilise the same harness.

The CCU treats the passenger door, and both rear doors as a single item. All door switches are earthed on B wires.

Bonnet Switch
In addition to the door switches, the CCU also monitors the condition of the bonnet switch. The bonnet switch is a normally open switch. When the bonnet is opened, the switch closes and an earth path is created.

The CCU (C0428) provides a feed to the bonnet switch (C0007) on an RP wire. The switch (C0007) is earthed on a B wire. By monitoring the state of the bonnet switch, the CCU can determine if the bonnet has been opened illegally and sound the alarm if necessary.

Roof On Switch (3 Door Vehicles Only)
The roof on switch (C0497) is located on the RH 'D' post, and is provided a constant battery feed by fuse 14 of the passenger compartment fuse box (C0580) on a P wire. The roof on switch is closed when the hard back is fitted, or the soft back is in the fitted position. In this instance, current flows across the switch (C0497) to the CCU (C0428) on a PY wire.

If the hard back is removed (or the soft back is folded down) the roof on switch becomes open circuit, and the feed to the CCU is removed. By monitoring the state of the roof on switch, the CCU can determine if the roof has been opened illegally and sound the alarm if necessary.

Anti-theft Alarm LED
Fuse 14 of the passenger compartment fuse box (C0589) provides a constant battery feed to the anti-theft alarm LED mounted in the instrument pack (C0230) on a P wire. The earth path for the LED (C0235) is controlled by the CCU (C0592) on a UK wire. By switching the earth path on and off, the CCU can control the flashing sequence of the LED.

Inertia Switch
Fuse 10 of the engine compartment fuse box (C0575) provides a constant battery feed to the inertia switch (C0123) on a G wire. The inertia switch is a normally closed switch. The inertia switch (C0123) is connected to the CCU (C0428) via the engine compartment fuse box by a GU then UG wire.

When the inertia switch is tripped the switch opens, cutting the voltage supply to the CCU. Sensing this, the CCU unlocks all doors and cuts the electrical supply to the fuel pump.

NOTE: The CCU will only unlock all doors if the ignition is switched on, and the anti-theft alarm isn't armed.

Volumetric Sensor
The CCU (C0429) provides a feed to the volumetric sensor (C0358 on 3 door vehicles, C1896 on 5 door vehicles) on a WB wire. When the alarm is armed, the volumetric sensor (C0358 on 3 door vehicles, C1896 on 5 door vehicles) returns a signal feed back to the CCU (C0428) on an NB wire. If the sensor detects movement within the vehicle, it withdraws the signal feed to the CCU. Sensing this, the CCU will sound the alarm.

The CCU (C0429) also provides a gain setting signal to the volumetric sensor (C0358 on 3 door vehicles, C1896 on 5 door vehicles) on an SW wire. This enables the volumetric sensor to determine if it is looking at the interior of a 3 door vehicle or a 5 door vehicle and adjust its sensitivity accordingly.

The volumetric sensor (C0358 on 3 door vehicles, C1896 on 5 door vehicles) is earthed on a B wire.

Radio Frequency (RF) Receiver
The CCU (C0429) provides a feed to the RF receiver (C0359) on a Y wire. The RF receiver (C0359) provides a 12 V feedback to the CCU (C0428) on an S wire. When an RF signal is received from the remote handset, the receiver switches the feed back to the CCU between 12 V and 0 V at high frequency.

The RF receiver (C0359) is earthed on a B wire.

Central Door Locking Switches
A non-latching CDL rocker switch is located in each front door switch pack. When the lock half of either switch is pressed, current is able to flow from the CCU (C0428) to the switch (C0328) on a BN wire. Current flows across the closed switch contacts to earth on a B wire. The CCU will now lock all the doors.

NOTE: The alarm will not be armed when using the master lock switch.

When the unlock half of the switch is pressed, current is able to flow from the CCU (C0428) to the master lock switch (C0328) on a BK wire. Current flows across the closed switch contacts to earth on a B wire. The CCU will now unlock all the doors.

NOTE: Both CDL rocker switches have the same connector number as they utilise the same harness.

Door Lock Motors
When the CCU receives a request to lock or unlock the doors, it powers the door lock motors as follows:

Driver Door
To lock the driver door, the CCU (C0430) provides a feed to the driver door lock motor (C0441) on a K wire. The motor (C0441) is provided an earth path via the CCU (C0430) on an O wire. This enables the motor to drive the latch to the lock position.

To unlock the driver door, the CCU (C0430) provides a feed to the driver door lock motor (C0441) on an O wire. The motor (C0441) is provided an earth path via the CCU (C0430) on a K wire. This enables the motor to drive the latch to the unlock position.

Passenger Door
To lock the passenger door, the CCU (C0430) provides a feed to the passenger door lock motor (C0441) on a K wire. The motor (C0441) is provided an earth path via the CCU (C0430) on an O wire. This enables the motor to drive the latch to the lock position.

To unlock the passenger door, the CCU (C0430) provides a feed to the passenger door lock motor (C0441) on an O wire. The motor (C0441) is provided an earth path via the CCU (C0430) on a K wire. This enables the motor to drive the latch to the unlock position.

NOTE: The driver and passenger door lock motors have the same connector numbers as they utilise the same harness.

LH Rear Door
To lock the LH rear door, the CCU (C0430) provides a feed to the LH rear door lock motor (C0442) on a K wire. The motor (C0442) is provided an earth path via the CCU (C0430) on an O wire. This enables the motor to drive the latch to the lock position.

To unlock the LH rear door, the CCU (C0430) provides a feed to the LH rear door lock motor (C0442) on an O wire. The motor (C0442) is provided an earth path via the CCU (C0430) on a K wire. This enables the motor to drive the latch to the unlock position.

RH Rear Door
To lock the RH rear door, the CCU (C0430) provides a feed to the RH rear door lock motor (C0442) on a K wire. The motor (C0442) is provided an earth path via the CCU (C0430) on an O wire. This enables the motor to drive the latch to the lock position.

To unlock the RH rear door, the CCU (C0430) provides a feed to the RH rear door lock motor (C0442) on an O wire. The motor (C0442) is provided an earth path via the CCU (C0430) on a K wire. This enables the motor to drive the latch to the unlock position.

NOTE: The LH rear and RH rear door lock motors have the same connector numbers as they utilise the same harness.

Tail Door
Operation of the tail door latch mechanism is only possible when the vehicle is stationary or travelling at speeds lower than 3 mph (5 km/h). To allow the tail door latch to operate, the CCU (C0430) provides a single voltage pulse to the tail door motor (C0617) on a PU wire. The motor (C0617) is earthed on a B wire.

The CCU receives a road speed signal from the ABS ECU. If road speed rises above 3 mph (5 km/h), the CCU will not provide a voltage pulse to the tail door motor, inhibiting operation of the tail door latch mechanism.

Superlocking
Superlocking inhibits the use of the interior door handles in addition to driving the door lock motors to the lock position. When the CCU receives a request to superlock the doors, it supplies the following outputs in addition to those detailed above in the Door Lock Motors description.

Driver Door
To superlock the driver door, the CCU (C0430) provides a feed to the driver door superlock motor (C0441) on an NK wire. The superlock motor (C0441) is provided an earth path via the CCU (C0430) on an O wire. This powers the superlock motor to the lock position, inhibiting the interior door handle.

To unlock the driver door from the superlock condition, the CCU (C0430) provides a feed to the driver door lock motor and the superlock motor (C0441) on an O wire. The driver door lock motor and the superlock motor (C0441) are provided an earth path via the CCU (C0430) on a K wire. This powers both motors to the unlock position.

Passenger Door
To superlock the passenger door, the CCU (C0430) provides a feed to the passenger door superlock motor (C0441) on an NK wire. The superlock motor (C0441) is provided an earth path via the CCU (C0430) on an O wire. This powers the superlock motor to the lock position, inhibiting the interior door handle.

To unlock the passenger door from the superlock condition, the CCU (C0430) provides a feed to the passenger door lock motor and the superlock motor (C0441) on an O wire. The passenger door lock motor and the superlock motor (C0441) are provided an earth path via the CCU (C0430) on a K wire. This powers both motors to the unlock position.

LH Rear Door
To superlock the LH rear door, the CCU (C0430) provides a feed to the LH rear door superlock motor (C0442) on an NK wire. The superlock motor (C0442) is provided an earth path via the CCU (C0430) on an O wire. This powers the superlock motor to the lock position, inhibiting the interior door handle.

To unlock the LH rear door from the superlock condition, the CCU (C0430) provides a feed to the LH rear door lock motor and the superlock motor (C0442) on an O wire. The LH rear door lock motor and the superlock motor (C0442) are provided an earth path via the CCU (C0430) on a K wire. This powers both motors to the unlock position.

RH Rear Door
To superlock the RH rear door, the CCU (C0430) provides a feed to the RH rear door superlock motor (C0442) on an NK wire. The superlock motor (C0442) is provided an earth path via the CCU (C0430) on an O wire. This powers the superlock motor to the lock position, inhibiting the interior door handle.

To unlock the RH rear door from the superlock condition, the CCU (C0430) provides a feed to the RH rear door lock motor and the superlock motor (C0442) on an O wire. The RH rear door lock motor and the superlock motor (C0442) are provided an earth path via the CCU (C0430) on a K wire. This powers both motors to the unlock position.

Horns
If the anti-theft alarm is triggered, the CCU (C0430) provides an earth path for the horn relay coil (C0576) on a PY wire. The energised horn relay (C0570 & C0576) provides a feed to the LH (C0003) and RH (C0004) horns on PB wires. The horns are earthed on B wires.

By switching the earth path for the relay coil on and off, the CCU can control the operation of the horns.

Direction Indicator/Hazard Warning Lamps
If the anti-theft alarm is triggered, the CCU (C0593) provides an earth path for the hazard warning relay coil. The energised hazard warning relay provides a feed to the following:
- The LH rear direction indicator lamp (C0928) on a GR wire
- The RH rear direction indicator lamp (C0837) on a GW wire
- The LH front direction indicator lamp (C0009) on a GR wire
- The RH front direction indicator lamp (C0011) on a GW wire
- The trailer pick-up (C0499) on a GR and GW wire.

All are earthed on B wires, except the trailer pick-up which is earthed on a W then B wire.

By switching the earth path for the relay coil on and off, the CCU can control operation of the direction indicator lamps.