Land Rover Defender Electrical Library 3rd Edition Nas Rover Manual

							CIRCUIT OPERATION
DEFENDER 90 NAS35CLOCK  
DESCRIPTION  
The analogue clock is located towards the center of the dash panel.  The clock is
illuminated when the sidelights are switched on.  
OPERATION  
Feed from the positive battery terminal is connected to the engine compartment fuse box
(C632-1) by the brown wire.  Current passes through fusible link 1 and fusible link 2 of
the engine compartment fuse box which are connected in series. Fusible link 2 of the
engine compartment fuse box (C574-3) provides a permanent power supply to the
analogue clock (C949-1) on the purple wire.  The clock is grounded (C950-1) on a black
wire.  
Illumination  
The analogue clock has illumination which operates with the sidelights.  Power from
fusible link 1 of the engine compartment fuse box passes through fusible link 4 of the
engine compartment fuse box (C573-2) and feeds the lighting switch (C41-1) on the
brown wire.  The lighting switch (C41-2) is connected to fuse 11 of the passenger
compartment fuse box (C581-1) by the red wire.  When the lighting switch is turned on,
power is supplied through fuse 11 (C581-2) to the dimmer circuit header joint (C285-7)
on the red/black wire - (See interior illumination).  Power flows through the dimmer
circuit (C285-16) to the clock illumination (C948-1) on the red/white wire.  The clock
illumination is grounded on a black wire.   
						

							CIRCUIT OPERATION
36DEFENDER 90 NASCIGAR LIGHTER  
DESCRIPTION  
The cigar lighter is located towards the center of the dash panel. Pressing the center of the
cigar lighter latches the heater element in to the holder. With the ignition switched on,
power flows through the heating element of the cigar lighter, causing it to heat up. When
the heating element reaches a sufficient temperature, the holder automatically releases the
cigar lighter which can then be removed for use.  
The location of the cigar lighter holder is illuminated when the sidelights are switched
on.  
OPERATION  
Feed from the positive battery terminal is connected to the engine compartment fuse box
(C632-1) by the brown wire.  Current passes through fusible link 1 and fusible link 5 of
the engine compartment fuse box which are connected in series. Fusible link 5 of the
engine compartment fuse box (C570-2) is connected to the ignition switch (C026-1) by
the brown wire.  
When the ignition switch is in position  II, current flows from the ignition switch (C94-1)
to fuse 19 of the passenger compartment fuse box (C581-13) on the white wire.  Fuse 19
(C581-18) is connected to the cigar lighter (C86-1) by the green/orange wire.  The cigar
lighter is grounded (C89-1) on a black wire.  
When the cigar lighter is pressed into its holder, locking clips secure it in position and
also connect the power supply to the heating element.  As the temperature of the heating
element rises, heat is transmitted to the holder, causing the locking clips to expand and
release the cigar lighter at a predetermined temperature.  
Illumination  
The cigar lighter has an illuminated ring which operates with the sidelights.  Power from
fusible link 1 of the engine compartment fuse box passes through fusible link 4 of the
engine compartment fuse box (C573-2) and feeds the lighting switch (C41-1) on the
brown wire.  The lighting switch (C41-2) is connected to fuse 11 of the passenger
compartment fuse box (C581-1) by the red wire.  When the lighting switch is turned on,
power is supplied through fuse 11 (C581-2) to the dimmer circuit header joint (C285-7)
on the red/black wire - (See interior illumination).  Power flows through the dimmer
circuit (C285-16) to the cigar lighter illumination (C74-1) on the red/white wire. The cigar
lighter illumination is grounded on a black wire.  
						

							CIRCUIT OPERATION
DEFENDER 90 NAS37IN-CAR ENTERTAINMENT   
DESCRIPTION  
The radio/cassette player operates when the ignition switch is in position I or II.  Signal
output from the radio/cassette player is relayed to four loud speakers via a power
amplifier. The radio/cassette player controls are illuminated when the unit is switched on.
The illumination dims when the sidelights are switched on.  
OPERATION  
Feed from the positive battery terminal is connected to the engine compartment fuse box
(C632-1) by a brown wire.  Current passes through fusible link 1 and fusible link 5 of the
engine compartment fuse box which are connected in series. Fusible link 5 (C570-2) is
connected to  the ignition switch  (C28-1) and fuse 2 of the passenger compartment fuse
box (C580-3) by brown wires.  Fuse 2 (C580-4) of the passenger compartment fuse box
supplies the radio/cassette player (C98-4) with a permanent feed on the purple wire.  The
permanent feed maintains the radio code and pre-set radio channels.  
With the ignition switch in position I or II, power flows through the ignition switch (C99-
1) to fuse 5 and fuse 6 (C580-7) of the passenger compartment fuse box on the
white/orange wire.  Fuse 6 (C580-12) supplies power to the power amplifier (C491/1&2)
on white/light green wires.  Fuse 5 (C580-10) supplies power to the radio/cassette player
(C98-7) on the white/pink wire. The radio/cassette player and power amplifier are
grounded on black wires.  
9 wires connect the radio/cassette player to the power amplifier.  These wires transmit the
audio signals from the radio/cassette player to the power amplifier.  The power amplifier
is connected to the 4 speakers as follows; 
RH front speaker by black/red (C491-14) and black/pink (C491-7) wires,  
LH front speaker by black/orange (C491-13) and black/yellow (C491-6) wires, 
LH rear speaker by black/blue (C491-11) and black/green (C491-4) wires, 
RH rear speaker by black/brown (C491-12) and black white (C491-5) wires.   
						

							CIRCUIT OPERATION
38DEFENDER 90 NASIllumination  
Fusible link 4 of the engine compartment fuse box (C573-2) is connected to the lighting
switch (C41-1) on the brown wire.  With the lighting switch in the on position, power
flows across the switch to fuse 11 of the passenger compartment fuse box (C581-1) on
the brown wire.  Fuse 11 (C581-2) supplies the radio/cassette unit illumination (C98-6)
on the red/black wire.  
						

							CIRCUIT OPERATION
DEFENDER 90 NAS39IGNITION AND SHIFT INTERLOCK  
DESCRIPTION  
Ignition interlock  
The ignition interlock prevents the following actions unless the gear selector lever is in
the Park position and the transfer box is in either High or Low range: 
· Key cannot be turned from position I to position 0. 
· Key can be turned to crank position III but starter motor will not operate.  
Shift interlock  
The shift interlock prevents the gear selector lever being moved from the Park position
unless the ignition key is in position II and the foot brake is applied.  
Transfer gearbox interlock  
The transfer gearbox interlock prevents the transfer box selector lever being moved unless
the ignition switch is in position II and the gear selector lever is in the Park or Neutral
position.  
OPERATION  
Feed from the positive battery terminal is connected to the engine compartment fuse box
(C632-1) by the brown wire.  Current passes through fusible link 1 and fusible link 5 of
the engine compartment fuse box which are connected in series. Fusible link 5 (C570-2)
is connected to the ignition switch  (C28-1) by the brown wire.  
Ignition interlock  
Fuse 2 of the engine compartment fuse box is connected in series with fusible link 1 of the
engine compartment fuse box.  Fuse 2 (C574-3) is connected to the key in sensor (C672-
1) by the purple wire. Inserting the key in to the ignition switch closes the key in sensor
and allows power to flow from the key in sensor (C672-2) to the key interlock solenoid
(C671-1) and diode (C924-2) on the brown/red wire. The diode prevents back feeding as
the solenoid energizes and de-energizes.
With the transfer gearbox in neutral, the transfer gearbox neutral switch will be closed.
With the neutral switch closed, current flows through the winding of the key interlock
solenoid (C671-2) on the brown/yellow wire, through the diode (C802-2 & 3), through
the switch (C684-3) to ground on the black wire and the solenoid remains energized,
preventing  the key being turned to position ‘0’ and, hence removed from the ignition. 
						

							CIRCUIT OPERATION
40DEFENDER 90 NASSimilarly, if the automatic transmission selector lever is not in park, the PARK 1 switch
will be closed and a ground path is provided for key interlock solenoid on the
brown/yellow wire, through the closed switch contacts, on the black wire (C668-4) &
(C550-6). Again, the key interlock solenoid will be energized an the key cannot be
removed.
Either, or both, of the above conditions will cause the key interlock solenoid to be
energized. Only with the transfer gearbox neutral switch open (in the HI or LO positions)
AND the automatic transmission selector lever in park, is the key interlock de-energized,
enabling the key to be moved to position ‘0’ and removed from the ignition.
Shift interlock  
The ignition switch (C94-1) is connected to fuse 18 of the passenger compartment fuse
box (C581-13) by the white wire.  With the ignition switch in position II, power flows
across fuse 18 (C581-14) to the brake pedal switch (C75-1) on the green/purple wire.
When the brake pedal is depressed, the switch closes and power flows across the switch
(C29-1) to the automatic transmission selector  (C668-2) on the green/purple wire. An
internal link connection takes the feed out of the selector (C668-5) on a pink/slate wire,
and back to the PARK 2 switch (C668-6). If the gear selector is in the Park position, the
route to ground for the gear shift interlock solenoid (C668-3) is provided on the black
wire.  With the gear shift interlock solenoid energized, the gear shift lever is released,
allowing the lever to be moved from the Park position. If the gear shift lever is not in the
Park position, the shift interlock solenoid has no continuity to ground and is not
energized.  With the shift interlock solenoid de-energized, the gear selector lever cannot
be moved from the Park position. Similarly, if the brake pedal switch is not closed by
depressing the brake pedal, power is not supplied to the gear shift interlock solenoid,
regardless of the gear selector lever position.   
Transfer gearbox interlock  
Fuse 2 of the engine compartment fuse box is connected in series with fusible link 1 of the
engine compartment fuse box.  Fuse 2 (C574-3) is connected to the key in sensor (C672-
1) by the purple wire. Inserting the key in to the ignition switch closes the key in sensor
and allows power to flow from the key in switch (C672-2) to the interlock relay winding
(C95-85) on the brown/red wire via a header joint (C289). If the automatic transmission
inhibitor switch is not in the neutral or park position, there is no ground path for the
interlock relay winding and the relay remains de-energized. In this condition, the transfer
gearbox selector lever cannot be moved. 
						

							CIRCUIT OPERATION
DEFENDER 90 NAS41With the automatic transmission inhibitor switch in either Park or Neutral, a ground path
is provided for the interlock relay winding (956-86), on the black/yellow wire, through the
diode (C801-1 & 2), through the closed switch contacts (C069- 5 & 4), to the
immobilization ECU on a black/orange wire (C057-10) and from the immobilization ECU
(C057-11) to ground on a black wire. With the relay energized, current flows from fuse
18 of the passenger compartment fuse box (C581-14) to the interlock relay (C956-87) on
a green wire. Current passes through the closed relay contacts (C956-30) to the transfer
gearbox interlock unit (C683-1) on the slate/black wire and to ground through the unit’s
solenoid winding on the black wire. In this condition, the unit is energized and the transfer
gearbox selector lever is free to move. 
						

							CONNECTOR DETAILS
DEFENDER 90 NASC1C1
DIRECTION
INDICATOR - LH
2 Way
Female
RED
Behind LH front indicator
lampCavColorCct1BALL2GRALL 
						

							   CONNECTOR DETAILS
DEFENDER 90 NASC2C2
DIRECTION
INDICATOR - RH
2 Way
Female
RED
Behind RH front indicator
lampCavColorCct1BALL2GWALL 
						

							CONNECTOR DETAILS
DEFENDER 90 NASC3C3
HORN
1 Way
Female
NATURAL
Under bonnet, LH inner
fenderCavColorCct1PBALL