LR3/Disco 3
GENERAL
The anti-lock control - traction control system is based on the 4 channel Bosch 8.0 system and provides the following
brake functions:
Anti-lock Braking System (ABS).
Corner Brake Control (CBC).
Dynamic Stability Control (DSC).
Electronic Brake-force Distribution (EBD).
Electronic Traction Control (ETC).
Emergency Brake Assist (EBA).
Engine Drag-torque Control (EDC).
Hill Descent Control (HDC).
The system consists of the following components:
A DSC switch.
An HDC switch.
An HDC relay.
A stoplamp switch.
Four wheel speed sensors.
A yaw rate and lateral acceleration sensor.
A steering angle sensor.
Warning indicators; four on vehicles with a high line instrument cluster and five on vehicles with a low line
instrument cluster.
A Hydraulic Control Unit (HCU) with attached ABS module.
DSC SWITCH
The DSC switch allows the DSC function to be selected off. Although Land Rover recommend that DSC is selected on for
all normal driving conditions, it may be beneficial to de-select DSC, to maximize traction, under the following conditions:
If the vehicle needs to be rocked out of a hollow or a soft surface.
Driving on loose surfaces or with snow chains.
Driving in deep sand, snow or mud.
On tracks with deep longitudinal ruts.
The DSC switch is a non-latching switch installed in the center switch pack on the instrument panel. Pressing the DSC
switch connects an ignition power feed to the ABS module. With the first press of the DSC switch, the ABS module
disables the DSC functions. When the DSC switch is pressed again, the ABS module re-enables the DSC functions. The
DSC switch must be pressed for a minimum of 0.3 s for the ABS module to react. The DSC function is re-enabled at the
beginning of each ignition cycle.
The status of the DSC switch selection is shown by the DSC warning indicator. The DSC warning indicator is off while
DSC is selected on, and continuously illuminated while DSC is selected off.
A DSC switch request to disable DSC is ignored if the air suspension system has failed, or is in off-road height at speeds
above 60 km/h (37.5 mph).
To guard against incorrect operation or a broken switch, if the input from the DSC switch is held high for more than one
minute, a failure is stored in the ABS module.
Even if DSC is deselected, driving manoeuvres with extreme yaw or lateral acceleration may trigger DSC activity to assist
3
-
Brake warning indicator (all except NAS)
4
-
DSC switch
5
-
HDC switch
6
-
HDC warning indicator (low line instrument cluster only)
7
-
HDC information indicator
8
-
DSC warning indicator
