ignition LAND ROVER DISCOVERY 1995 Repair Manual

STEERING
15
REPAIR STEERING COLUMN LOCK ASSEMBLY
Service repair no - 57.40.31
Remove
CAUTION: Before removing any parts of
steering linkage, it is imperative that road
wheels are positioned straight ahead.
Then steering wheel removed to prevent rotary
coupler being wound up or damaged.
CAUTION: After refitting steering linkage
parts follow correct procedure to ensure
that road wheels, steering box and
steering wheel are correctly positioned relative to
each other when in straight ahead condition. If
steering wheel requires repositioning, ensure that
drive pegs on rotary coupler are correctly
positioned before steering wheel is replaced.
This ensures drive pegs locate in their holes in
rear of steering wheel.
After final alignment connect rotary coupler
multiplug, tighten steering wheel securing nut and
fit airbag module - if fitted.
1.Disconnect battery negative lead.
2.Remove steering column shroud.
See Steering
Column Shroud
3.Release turnbuckles, lower driver's access
panel.
4.If fitted, remove 4 screws securing knee pad,
remove bolster.
5.Disconnect ignition switch multiplug from fuse
box.
6.Disconnect ignition switch main feed multiplug.

BRAKES
19
REPAIR SENSORS - REAR
Service repair no - 70.65.31
CAUTION: If a sensor is removed for any
reason, a NEW sensor bush must be fitted.
Remove
1.Disconnect battery negative lead.
2.Disconnect sensor electrical connections,
located above rear axle.
3.Remove sensor from its locating clip.
4.Remove bolts securing mudshield.
5.Using a suitable lever, pry sensor from mounting
bush.
6.Release harness cable ties, remove sensor lead
from vehicle.
7.Remove sensor bush.
Refit
8.Fit new sensor bush.
9.Lightly grease new sensor using silicone grease.
See LUBRICANTS, FLUIDS AND
CAPACITIES, Information, Recommended
Lubricants and Fluids
10.Push sensor through bush until it touches exciter
ring. Sensor will be 'knocked back' to correct
position when vehicle is driven.
11.Secure harness in position.
12.Reconnect sensor electrical connection.
13.Drive vehicle to ensure ABS warning light is
extinguished.STOP LIGHT SWITCH ABS
Service repair no - 86.65.51
Remove
1.Turn ignition off. Disconnect battery negative
lead.
2.Remove lower trim panel.
3.Disconnect multiplug to switch.
4.Depress brake pedal access front of switch.
5.Pull sleeve and plunger of switch FULLY
forward.
6.Remove switch rearwards
NOTE: If switch is difficult to release,
check sleeve is FULLY forward.
Refit
7.Pull sleeve and plunger of switch fully forward.
8.Depress brake pedal, fit switch. Ensure retaining
clips are FULLY located.
9.Hold switch firmly in place, pull brake pedal back
fully to set switch.
10.Reconnect battery and turn ignition on.
11.Check switch operation by slowly depressing
brake pedal and checking that the switch clicks
twice.
12.Check stop lamps go off when pedal is released.
13.Recheck switch is securely fitted.
14.Operation may be checked using Testbook.

SUPPLEMENTARY RESTRAINT SYSTEM
5
DESCRIPTION AND OPERATION
7.Do not use electrical test equipment on the
airbag harness or connectors. Tampering with or
disconnecting the harness could result in
accidental firing of the airbag or make the
system inoperative, which may result in serious
injury.
8. An airbag system fault can only be
diagnosed using TestBook.
9.The airbag module contains Sodium Azide which
is poisonous and extremely flammable. Contact
with water, acid or heavy metals may produce
harmful or explosive compounds. Do not
dismantle, incinerate or bring into contact with
electricity.VEHICLE RECOVERY
Towing - airbag not deployed
Normal towing procedures are unlikely to cause an
airbag to deploy. However, as a precaution switch the
ignition off and then disconnect both battery leads.
Disconnect the negative '-' lead first.
Towing - airbag deployed
Once the driver's airbag has been deployed the
vehicle must have a front suspended tow. However,
as a precaution switch the ignition off and then
disconnect both battery leads. Disconnect the
negative '-' lead first.

SUPPLEMENTARY RESTRAINT SYSTEM
1
REPAIR SYSTEM PRECAUTIONS
CAUTION: Before and during any removal
operations within the SRS section, note
routing and position of all harnesses to aid
correct refitting and to avoid accidentally trapping
cables.
CAUTION: During refitting of any item
within the SRS section, always ensure
connectors are fully engaged and latched
before proceeding to the next stage of the
operation.DRIVER'S AIRBAG MODULE
Service repair no - 76.74.01
WARNING: All the airbag system
components, including the wiring harness,
MUST be renewed after the airbags have
deployed.
Remove
1.Turn steering wheel 90Ê from horizontal.
2.Switch off ignition.
3.Disconnect battery negative '-' and then the
positive '+' lead.
CAUTION: Always disconnect both leads.
4.Release 2 turnbuckles and remove dash lower
panel.

SUPPLEMENTARY RESTRAINT SYSTEM
9
REPAIR PASSENGER'S AIRBAG MODULE
Service repair no - 76.74.02
WARNING: All the airbag system
components, including the wiring harness,
MUST be renewed after the airbags have
deployed.
Remove
1.Switch off ignition.
2.Disconnect battery negative lead and then
positive lead.
3.Open glovebox and disconnect harness
connector from airbag module.
4.Use special socket and long extension, remove
2 torx head screws securing front of airbag
module to fascia panel.
5.Use special socket, remove 2 torx head screws
securing rear of airbag module to fascia panel.
6.Release airbag module from fascia panel.
CAUTION: Do not allow the airbag module
to hang by the airbag harness.
7.Carefully and without pulling on connector
remove airbag module.
CAUTION: Store the airbag module in
accordance with the storage procedures
described in Description and Operation.
NOTE: If airbag module is to be replaced
the serial number must be recorded in the
vehicle service record.
Refit
8.Reverse removal procedure.
9.Tighten airbag module securing screws to
8Nm
(6 lbf ft).
CAUTION: Take care not to cross thread
screws.
10.Check Supplementary Restraint System using
Testbook.

AIR CONDITIONING
5
DESCRIPTION AND OPERATION Condenser cooling fans
The condenser cooling fans operate automatically
whenever the air conditioning system is switched on.
Fan timer unit
The thermostatically controlled timer will continue to
operate the cooling fans after the air conditioning or
ignition is switched off. When the system temperature
is excessive, the fans will operate for 10 minutes to
reduce condenser and underbonnet temperature.
Blower control
The blower can be operated at any one of four speeds
by sliding the blower switch to the required position.
When the blower is switched off the air conditioning
system will not operate.
The fresh air/recirculation flaps can move between
two positions. One position covers the outside air
inlet, leaving open an inlet from the inside of the
vehicle clear, when recirculated air is required. In the
other position they will cover the inlet from the inside
of the vehicle leaving open the outside air inlet when
fresh air is required.Heater distribution and blend unit control
Blower unit air flow, having passed through the
evaporator passes into the heater blend unit to be
heated, if required. It is then directed into the vehicle
interior in accordance with the flap positions
designated by the air distribution control. Heater flaps
control the amount of air flowing through the heater
matrix. These flaps are controlled individually by the
driver's and passenger's temperature controls.
When the temperature control is in the cold position, a
micro switch actuates a vacuum control to close the
coolant valve on the engine. As the temperature
control is moved away from cold, the coolant valve is
opened allowing heated engine coolant to flow
throught the heater matrix. The temperature of the
heated air flow into the vehicle interior is controlled by
the blend flaps.
The distribution control moves the flaps which control
the direction of the air flow into the interior of the
vehicle.

82AIR CONDITIONING
6
ADJUSTMENT SYSTEM TEST
1.Place the vehicle in a ventilated, shaded area
free from excessive draught, with the doors and
windows open.
2.Check that the surface of the condenser is not
restricted with dirt, leaves, flies, etc. Do not
neglect to check the surface between the
condenser and the radiator. Clean as necessary.
3.Switch on the ignition and the air conditioner air
flow control. Check that the blower is operating
efficiently at low, medium and high speeds.
Switch off the blower and the ignition.
4.Check that the evaporator condensate drain
tubes are open and clear.
5.Check the tension of the compressor driving belt,
and adjust if necessary.
6.Inspect all connections for the presence of
refrigerant oil. If oil is evident, check for leaks,
and repair as necessary.
NOTE: The compressor oil is soluble in
Refrigerant R134a and is deposited when
the refrigerant evaporates from a leak.
7.Start the engine.
8.Set the temperature controls to cold and switch
the air conditioner blower control on and off
several times, checking that the magnetic clutch
on the compressor engages and releases each
time.9.With the temperature control at maximum
cooling and the blower control at high speed,
warm up the engine and fast idle at 1000
rev/min. Check the sight glass for bubbles or
foam. The sight glass should be generally clear
after five minutes running, occasional bubbles
being acceptable. Continuous bubbles may
appear in a serviceable system on a cool day, or
if there is insufficient air flow over the condenser
at a high ambient temperature.
10.Repeat at 1800 rev/min.
11.Gradually increase the engine speed to the high
range, and check the sight glass at intervals.
12.Check for frosting on the service valves.
13.Check the high pressure hoses and connections
by hand for varying temperature. Low
temperature indicates a restriction or blockage at
that point.
14.Switch off the air conditioning blower and stop
the engine.
15.If the air conditioning equipment is still not
satisfactory, carry out a pressure test as
previously described in this section.
COMPRESSOR DRIVE BELT
Service repair no - 82.10.01.
Tdi -
See ENGINE, Repair, Compressor drive belt
V8i and MpiSee ENGINE, Repair, Drive belt

84WIPERS AND WASHERS
2
DESCRIPTION AND OPERATION Wash wipe function
With the ignition switched on, power is supplied via a
fuse to the multi-switch, a control unit and a park
switch which is driven by the wiper motor.
Single wipe A
Pull the lever down and release immediately.
NOTE: With the lever held down, the
wipers will continue operating at high
speed until it is released.
Intermittent wipe B
Turn switch to second position.
Normal speed wipe C
Turn switch to second position.
Fast speed wide D
Turn switch to third position.
Variable delay (intermittent wipe)
Rotate the switch to vary the delay between wipes.
Windscreen washer E
Pull the lever towards the steering wheel. The
windscreen washers will operate in conjunction with
the wipers for as long as the lever is held in this
position.
Headlamp washers
The headlamp washers operate automatically
whenever the windscreen washers are operated,
provided the headlamps are illuminated and switched
to dipped beam. For continuous washing, hold the
windscreen washer control in the washposition E.
REAR WINDOW WIPER AND WASHER
OPERATION
The illustration J5375 also locates and identifies the
main components of the rear window wiper and
washer system which is operated by two switches
mounted on the right hand side of the instrument
binnacle.
Rear window wipe A
Press the switch to operate: after continuously wiping
3 or 4 times, the wiper operates intermittently (approx
once every 6 seconds) until switched off.
Rear window washer B
Press and hold the switch for the required duration of
rear screen washing. The wiper operates
automatically during washing and continues for a
further 3 wipes after the switch is released.

ELECTRICAL
1
DESCRIPTION AND OPERATION ELECTRICAL EQUIPMENT
DESCRIPTION
The electrical system is Negative ground, and it is
most important to ensure correct polarity of the
electrical connections at all times. Any incorrect
connections made when reconnecting cables may
cause irreparable damage to the semi-conductor
devices used in the generator and regulator. Incorrect
polarity would also seriously damage any
transistorized equipment such as radio and
tachometer etc.
WARNING: During battery removal or
before carrying out any repairs or
maintenance to electrical components
always disconnect the battery negative lead first.
If the positive lead is disconnected with the
negative lead in place, accidental contact of the
wrench to any grounded metal part could cause a
severe spark, possibly resulting in personal
injury. Upon installation of the battery the positive
lead should be connected first.
GENERATOR
The generator is a three phase, field sensed unit. The
rotor and stator windings produce three phase
alternating current, AC, which is rectified to direct
current, DC. The electronic voltage regulator unit
controls the generator output voltage by high
frequency switching of the rotor field circuit. Use only
the correct Vehicle replacement fan belt. Occasionally
check that the engine and generator pulleys are
accurately aligned.
It is essential that good electrical connections are
maintained at all times. Of particular importance are
those in the charging circuit (including those at the
battery) which should be occasionally inspected to
see that they are clean and tight. In this way any
significant increase in circuit resistance can be
prevented.Do not disconnect battery cables while the engine is
running or damage to the semi-conductor devices
may occur. It is also inadvisable to break or make any
connections in the generator charging and control
circuits while the engine is running.
The electronic voltage regulator employs micro-circuit
techniques resulting in improved performance under
difficult service conditions. The whole assembly is
encapsulated in silicone rubber and housed in an
aluminium heat sink, ensuring complete protection
against the adverse effects of temperature, dust, and
moisture etc.
The regulating voltage is set during manufacture to
give the required regulating voltage range of 14.2±
0.2 volts, and no adjustment is necessary. The only
maintenance needed is the occasional check on
terminal connections and wiping with a clean dry
cloth.
The generator system provides for direct connection
of a charge (ignition) indicator warning light, and
eliminates the need for a field switching relay or
warning light control unit. As the warning lamp is
connected in the charging circuit, lamp failure will
cause loss of charge. Lamp should be checked
regularly and spare carried.
When using rapid charge equipment to re-charge the
battery, the battery must be disconnected from the
vehicle.
NOTE: For description and operation of
electrical circuits see separate publication:
Electrical Troubleshooting Manual.

86ELECTRICAL
2
DESCRIPTION AND OPERATION ANTI-THEFT SYSTEM FUNCTION
Perimetric protection
Using the key in the correct sequence will turn on and
off perimetric protection only. When fully perimetrically
armed, all doors, and bonnet [hood] are protected
against unauthorised access. If the door key is used in
the normal manner the driver will be unaware of the
door key sequence. The time taken to lock or unlock
with the key must be less than 5 seconds. To prevent
unauthorised tampering, the alarm will sound if the
key is held in the unlocked position for longer than 5
seconds when armed. Cranking is disabled when
perimetric protection is armed.
NOTE: When key is turned left or right the
keyswitch input will be activated, in
conjunction with the sill button switch
when links are operated.
Volumetric protection
Using the handset transmitter will turn on and off
volumetric protection. In volumetric mode the vehicle
interior is protected using the ultrasonic sensor. Using
the handset also arms and disarms the vehicle
perimetrically. Cranking is disabled when volumetric
and perimetric protection is armed.
NOTE: If armed volumetrically the vehicle
CANNOT be disarmed using the key.
Alarm horn
When an intrusion is detected the alarm horn will
sound intermittently (Switzerland and Denmark
continuous horn sound) and the hazard lights flash
(where territorial regulations allow) for 30 seconds.
The alarm must be retriggered before alarm horn will
sound again.Vehicle status indication
Vehicle status is indicated by up to three devices: (a)
alarm horn, (b) hazard lights, (c) dash board LED.
When the vehicle arms in either mode the hazard
lights will flash three times and the LED will flash
rapidly for 10 seconds. LED will then flash at a slower
rate while vehicle is armed. When the vehicle disarms,
hazard lights will flash once and LED will extinguish. If
LED remains lit, it indicates that the alarm has been
triggered. Turning on ignition or arming the alarm will
extinguish LED. The LED will give a long pulse flash
to indicate the ultrasonic unit being activated.
Central locking
Central locking is controlled by the alarm ECU and
may be operated by the key, sill button(s) or handset.
The system works on both front doors on four door
vehicles or driver's door on two door vehicles.
NOTE: The central door locking system
will shut down for a short period after
more than 15 consecutive operations.
Inertia switch
An inertia switch is incorporated in the alarm system
ECU. If ignition is on and the vehicle receives an
impact sufficient to activate the inertia switch, the ECU
will signal to unlock central locking actuators and flash
hazard lights. Central locking will remain disabled for
30 seconds. To reset turn ignition off and then on after
the 30 second period has elapsed.
Ultrasonic unit
The unit operates by emitting an air pressure carrier
wave and receiving the wave back. Any disturbance
within the vehicle which disturbs the wave will be
detected, triggering the alarm.
When the volumetric sensor is activated it monitors
movement within the vehicle for 15 seconds before
detecting and responding to intrusions. If the sensor
detects movement within the vehicle it delays arming
until a 15 seconds quiet period has elapsed. If
continuous movement is detected the alarm will not
arm volumetrically.