Discovery II
INSTRUMENTS
DESCRIPTION AND OPERATION
88-21
Hill Descent Control (HDC) information warning lamp
The HDC information warning lamp within the instrument pack utilises a green LED and a clear legend. On vehicles
fitted with HDC, the HDC switch provides a hard wired voltage to the SLABS ECU to illuminate the LED when HDC
is switched on. This provides the driver with a visible warning that the system is enabled.
When the ignition is switched on, the SLABS ECU illuminates the LED to provide a self-check, providing there is no
fault it will remain illuminated for 3 seconds or until the ignition is switched off.
The power input for the LED is supplied by the instrument pack via fuse 27. The SLABS ECU provides the earth path
to illuminate the warning lamp.
The voltage on the SLABS ECU earth path to the instrument pack is as follows:
l
< 1.8 volts = warning lamp on.
l
> 7.7 volts = warning lamp off.