Central Door Locking (CDL) (Body control unit)

Alarm system The alarm system comprises the following components: l RF receiver. l RF transmitter. l BCU. l IDM. l Door switches, door lock switches and bonnet switch. l Battery backed-up sounder (BBUS). l Status LED.

On non NAS vehicles, power supply for the alarm sounder and the battery BBUS is provided through two relays in the passenger compartment fuse box. Each of the coils of the alarm relays are directly connected to the IDM which controls their operation under the direction of BCU signals received via the serial data bus.

On NAS vehicles, an audible warning is provided through operation of the vehicle horns. The BCU provides an earth path for the coil of the horn relay to initiate vehicle horn operation. ALARM SYSTEM AND HORN, DESCRIPTION AND OPERATION, Description.

Central Door Locking (CDL)

The BCU carries out the logic control operation for CDL. A CDL switch is mounted on the fascia panel and has two inputs to the BCU, one for lock and one for unlock.

Door locking and unlocking can be performed using the remote transmitter in the keys and the receiver unit located above the vehicle's headlining, behind the rear sunroof aperture. The receiver detects the signals sent from the remote transmitter and sends a decoded signal to the BCU for processing.

Four methods of door locking are available: l Remote handset locking. l Vehicle key locking. l CDL switch locking. l Speed related locking.

Two security levels of door locking are available, CDL and Superlocking. The anti-theft alarm system works in conjunction with the CDL system.

Electric windows and sunroof

The BCU controls the logical operations and the timing periods for the electric front windows. The rear windows are hard-wired and the two electric sunroofs are controlled by a dedicated ECU which is enabled by the BCU.

The front windows are electrically operated using two rocker switches located in the centre console. Electric motors are located in each of the front doors.

The rear windows are enabled by the IDM controlling the operation of the rear window relay located in the passenger compartment fuse box.

Wipers and washers

The wiper and washer functions are controlled by the BCU and the IDM.

The front wipers and washers are operated from the switch stalk located on the right hand side of the steering column and only operate when the ignition switch is in position I or II. The front wipers are operated by a motor located below the windscreen plenum. WIPERS AND WASHERS, DESCRIPTION AND OPERATION, Description.