Land Rover Discovery 99my To 03my Electrical Library 3rd Edition Rover Manual

DESCRIPTION AND OPERATION
4.120DISCOVERY SERIES II
Front Fog Lamps Operation
When the front fog lamp switch is operated, an earth path is completed from the BCU pin 
C0660-7 to the switch on a KB wire. The earth path continues through the switch contacts 
and is connected to earth header C0017 LHD/C0018 RHD on a B wire, via header C0760.
The completion of the earth path signals the BCU to provide an earth path from the coil of 
the front fog lamp relay in the engine compartment fusebox to the BCU pin...

DESCRIPTION AND OPERATION
DISCOVERY SERIES II 4.121
REAR FOG GUARD LAMPS
DESCRIPTION
General
The rear fog guard lamps are controlled by a non-latching switch located on the left side of 
the instrument pack. The lamps are located in the rear bumper, adjacent to the indicator 
lamps. Rear fog guard lamp operation is monitored by the Body Control Unit (BCU) which 
only allows the lamps to operate when the side lamps or headlamps are on and the front fog 
lamps are switched on.
When the side lamps,...

DESCRIPTION AND OPERATION
4.122DISCOVERY SERIES II
Ignition switch supply
With the ignition switch in position II, the feed from fusible link 8 flows through the ignition 
switch to the passenger compartment fusebox on a Y wire. The feed continues through fuse 
29 in the passenger compartment fusebox and is connected to one of the two electronic 
switch in the IDM.
In this condition, one of two switches in the IDM closes. The earth path from the IDM is 
connected from the passenger compartment fusebox to...

DESCRIPTION AND OPERATION
DISCOVERY SERIES II 4.123
From the connector interface C0905-2/C0020-2, the feed is connected on a Y wire to 
connector interface C0905-3/C0020-3. From this interface the feed is connected on an RY 
wire to header C0295.
A feed from header C0295 is connected on an RY wire to the RH rear fog guard lamp which 
in turn is connected to earth header C0706 on a B wire.
A second feed from header C0295 is connected on a RY wire to the LH rear fog guard lamp 
which in turn is connected...

DESCRIPTION AND OPERATION
4.124DISCOVERY SERIES II
INDICATORS AND HAZARDS
DESCRIPTION
General
The direction indicator lamps are operated from a three position direction indicator switch 
located on the left hand side of the steering column and only operate with the ignition switch 
in position II. Left and right indicator lights in the instrument pack flash accordingly to show 
correct flasher operation. If a failure of an indicator bulb occurs, the appropriate flasher 
symbol on the instrument pack will...

DESCRIPTION AND OPERATION
DISCOVERY SERIES II 4.125
OPERATION
Direction Indicators and Hazard Warning Lamps Supply
Circuit supply
A feed from the battery positive terminal is connected by an R wire to the engine 
compartment fusebox, where it passes through fusible link 8 and fuse 14.
A feed from fuse 14 is connected to the passenger compartment fusebox on a PN wire 
where it is connected to the contacts and coils of the RH and LH indicator relays in the 
fusebox.
A feed from fusible link 8 is connected...

DESCRIPTION AND OPERATION
4.126DISCOVERY SERIES II
The resistor is used by the IDM to monitor the current drawn through the resistor by the 
direction indicator bulbs. If an indicator bulb fails, the IDM detects the drop in current draw 
across the resistor and operates the flasher relay at a faster speed. The faster flash is also 
transmitted to the instrument pack to inform the driver of the bulb failure.
The IDM operates the direction indicator lamps in the instrument pack on the serial data bus 
on...

DESCRIPTION AND OPERATION
DISCOVERY SERIES II 4.127
RH rear
The feed is connected from header C0289, via header C0723, on a GW wire to the RH rear 
direction indicator/hazard warning lamp. The lamp is connected on a B wire to earth header 
C0706.
RH Side repeater
The feed is connected from header C0289 on a GW wire to the RH RH front side repeater 
lamp. The lamp is connected on a B wire, via header C1000, to earth eyelet connector 
C0558-1.
Trailer connection
The feed for the trailer connection is taken...

DESCRIPTION AND OPERATION
4.128DISCOVERY SERIES II
The IDM operates both direction indicator lamps in the instrument pack on the serial data 
bus on the SK wire from the passenger compartment fusebox, via header C0293 LHD/
C0292 RHD, to the instrument pack.
The hazard warning lamp operation is the same as that described for the direction indicator 
lamps operation. 

DESCRIPTION AND OPERATION
DISCOVERY SERIES II 4.129
INTERIOR LAMPS
DESCRIPTION
General
Interior illumination is provided by front, rear and load space lamps, ignition switch 
illumination, vanity mirror illumination and also includes an electrically operated interior rear 
view mirror (if fitted).
The front, rear and load space lamps and the ignition illumination operate from a direct feed 
from the battery, independent of the ignition switch position. The vanity mirrors and the 
interior rear view...