1995 LAND ROVER DISCOVERY warning light

AIR CONDITIONING
1
REPAIR PRECAUTIONS IN HANDLING REFRIGERANT
LINES
WARNING: Wear eye and hand protection
when disconnecting components
containing refrigerant. Plug all exposed
connections immediately.
1.When disconnecting any hose or pipe
connection the system must be discharged of all
pressure. Proceed cautiously, regardless of
gauge readings. Open connections slowly,
keeping hands and face well clear, so that no
injury occurs if there is liquid in the line. If
pressure is noticed, allow it to bleed off slowly.
2.Lines, flexible end connections and components
must be capped immediately they are opened to
prevent the entrance of moisture and dirt.
3.Any dirt or grease on fittings must be wiped off
with a clean alcohol dampened cloth. Do not use
chlorinated solvents such as trichloroethylene. If
dirt, grease or moisture cannot be removed from
inside the hoses, they must be replaced with
new hoses.
4.All replacement components and flexible end
connections must be sealed, and only opened
immediately prior to making the connection.
5.Ensure the components are at room temperature
before uncapping, to prevent condensation of
moisture from the air that enters.
6.Components must not remain uncapped for
longer than fifteen minutes. In the event of delay,
the caps must be fitted.
7.Receiver/driers must never be left uncapped as
they contain Silica Gel crystals which will absorb
moisture from the atmosphere. A receiver/ drier
left uncapped must not be used, fit a new unit.
8.The compressor shaft must not be rotated until
the system is entirely assembled and contains a
charge of refrigerant.
9.A new compressor contains an initial charge of
of refrigerant oil. The compressor also contains a
holding charge of gas when received which
should be retained by leaving the seals in place
until the pipes are re-connected.10.The receiver/drier should be the last component
connected to the system to ensure optimum
dehydration and maximum moisture protection of
the system.
11.All precautions must be taken to prevent
damage to fittings and connections. Slight
damage could cause a leak with the high
pressures used in the system.
12.Always use two wrenches of the correct size,
one on each fitting when releasing and
tightening refrigeration unions.
13.Joints and 'O' rings should be coated with
refrigeration oil to aid correct seating. Fittings
which are not lubricated with refrigerant oil are
almost certain to leak.
14.All lines must be free of kinks. The efficiency of
the system is reduced by a single kink or
restriction.
15.Flexible hoses should not be bent to a radius
less than 90mm.
16.Flexible hoses should not be within 100mm of
the exhaust manifold.
17.Completed assemblies must be checked for
refrigeration lines touching metal panels. Any
direct contact of lines and panels transmits noise
and must be eliminated.

AIR CONDITIONING
11
REPAIR THERMOSTAT
Service repair no - 86.25.50
Remove
1.Remove heater and cooler unit.
See Heater
and Cooler Unit
2.Remove lower cover and evaporator.See
Evaporator and Expansion Valve
3.Remove 5 clips and screw securing evaporator
top cover.
4.Remove evaporator top cover.
5.Remove thermostat sensor from evaporator
matrix.
6.Remove 2 screws securing sensor unit.
7.Remove thermostat and insulation.
Refit
8.Reverse removal procedure.
CAUTION: The thermostat insulation must
be installed in the ORIGINAL POSITION in
the evaporator.EVAPORATOR/BLOWER MOTOR ASSEMBLY -
REAR
Service repair no - 82.26.01
Remove
1.Recover refrigerant from system.
See
Adjustment, refrigerant recovery recycling
recharging
WARNING: Wear eye and hand protection
when disconnecting components
containing refrigerant. Plug all exposed
connections immediately.
2.Remove evaporator to alpine light duct.
See
evaporator to alpine light duct
3.Remove LH rear mud flap.See CHASSIS AND
BODY, Repair, mud flap - rear - lh
4.Clean area around low and high pressure air
conditioning pipe unions, beneath rear wheel
arch, to prevent any risk of dirt entering the
system.
5.Loosen and disconnect high and low pressure
air conditioning pipe unions beneath rear wheel
arch.
6.Remove and discard 'O' rings from pipe unions.
CAUTION: Use 2 spanners when loosening
or tightening air conditioning pipe unions.
CAUTION: Plug exposed connections
immediately.

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.

ELECTRICAL
3
DESCRIPTION AND OPERATION Radio frequency system
The RF system uses four frequencies according to
market. If the coaxial aerial is not fitted system
performance will be impaired. Both ECU and handset
have a colour coded label.
Frequency Colour Territory
ECU/Handset
433.92 MHz Blue/black........................... UK, Ireland........................
224.5 MHz, Yellow/yellow............................ France...................
433.92 MHz Blue/Purple........................... Germany......................
433.92 MHz Blue/blue........................... Europe, not France, Switzerland, Italy, Denmark,..........................
Germany
433.92 MHz White/Blue........................... Switzerland, Denmark.......................
315.0 MHz Green/green............................. Rest of world, Italy, Australia....................
315.0 MHz Orange/Green............................. Gulf, Japan..................
Partially armed mode
If a door, tailgate or bonnet [hood] is left open when
the system is armed, the LED will not light for 10
seconds indicating a mislock condition. Hazard lights
will not flash. If an open door or tailgate is causing the
mislock, the starter motor is disabled. The alarm will
sound if ignition is turned to start position. If an open
bonnet [hood] is causing the mislock the starter motor
is disabled. The alarm will arm the volumetric part of
the system. If the door tailgate or bonnet [hood] is
subsequently closed, after a 5 second delay, the
doors will unlock and immediately lock and the system
will fully arm.
Handset transmitter
The handset LED will give one short flash when
button is pressed momentarily.
If button is held down the LED will light again after 2
seconds for 2 seconds, and extinguish until button is
released and repressed. The handset contains unique
information distinguishing it from other transmitters. It
also contains a set of 'random' rolling codes
programmed into the ECU before leaving the factory.
Each time the handset is pressed a different code is
transmitted to the ECU.
If handset is operated more than four times outside
the vehicle range (6 metres) or power supply is
removed, it will be necessary to re-sychronise handset
and the ECU by pressing the handset three times
within range and within 5 seconds.
NOTE: If both handsets are lost or
damaged when system is armed it will be
necessary to fit a new ECU with two
matching handsets.
Handset batteries
If handset LED flashes continuously when button is
pressed, the batteries need replacing. The hazard
lights will flash one 3 second pulse, instead of three
times upon arming vehicle.
Power up mode
The alarm system always remembers the state it was
left in when power was removed. If the alarm powers
up in an armed state and is subsequently triggered it
will give a warning that it will fully trigger unless
disarmed. This warning consists of short horn pulses
every two seconds for 15 seconds.
New born mode
When the ECU is first produced, it will be in its 'new
born' mode. In this mode it will respond to any remote
of the right frequency. This mode will be cancelled
when the ECU has received ten valid handset signals
without power interruption.
Engine cranking
It is only possible to crank the engine when ignition is
ON and alarm disabled.

86ELECTRICAL
6
DESCRIPTION AND OPERATION ALARM COMPONENT LOCATIONS (96 MODELS)
COMPONENT LOCATION
1. Electronic control unit (ECU) and relays Under dash (passenger side).................
2. Anti-theft alarm indicator light Instrument panel..................................
3. Engine immobilisation warning light (EIWL) * Instrument panel..........
4. Passive coil Over starter switch barrel.............................................................
5. Bonnet switch RH engine compartment..........................................................
6. Door switches
7. Ultrasonic sensor Interior light switch panel....................................................
8. Lock barrel, sill buttons
9. Handset and key
10. Battery backed-up sounder or horn * RH engine compartment......................
11. Immobilisation unit (spider) * Above heater...................................
12. Aerial Part of fascia harness.......................................................................
* where applicable

86ELECTRICAL
8
DESCRIPTION AND OPERATION DETECTION COMPONENTS
Switches
Perimetric protection for the vehicle is provided by
ECU inputs connected to the following:
Key switches (including starter)
Sill buttons
Bonnet switch
Door switches
Ultrasonic sensor
The ultrasonic sensor is located on the interior light
switch panel and triggers the alarm if movement is
detected.
WARNING INDICATORS
Battery backed-up sounder
The battery backed-up sounder is located in the
engine compartment and provides an audible warning
whenever the alarm is triggered.
NOTE: Disconnecting the vehicle battery
will result in the alarm sounding if the
correct procedure has not been followed.
See Repair, Battery.
Engine immobilisation warning light (EIWL)
The engine immobilisation warning light is located in
the instrument pack and provides a visual indication
that the engine is immobilised.
Anti-theft alarm indicator light
The anti-theft alarm indicator light is located in the
instrument pack and provides a visual indication of the
alarm status.
Inertia switch and central door locking
As a safety feature, the alarm system is designed to
recognise the inertia switch and via the ECU, unlock
the doors in the event of a collision.
NOTE: This feature only applies when the
starter switch is in the on position.ANTI-THEFT ALARM OPERATION (96 MODELS)
Full arming and immobilisation
Locking the vehicle using the handset immobilises the
engine and initializes both volumetric and perimetric
protection, providing:
1.After a lock signal has been received, a period of
15 seconds has elapsed during which no
movement is detected inside the vehicle;
2.No door or bonnet is open.
NOTE: If either of the above conditions are
not satisfied, the alarm will only be
partially armed. This is a mislock condition
which will be made apparent by a delay of 10
seconds before the anti-theft alarm indicator
begins to flash.
Disarming the alarm
NOTE: ALWAYS disarm the alarm using
the handset.
Unlocking with the key will not disarm the alarm or
mobilise the vehicle. If the handset fails to unlock the
vehicle
See Repair, Handset.
Partial arming and immobilisation
The alarm will be partially armed and the engine
immobilised if the vehicle is locked with the handset or
key, if:
1.After a lock signal has been received, a period of
15 seconds has elapsed during which movement
is detected inside the vehicle;
2.A door or bonnet is open.
NOTE: This is a mislock condition which
will be made apparent by a delay of 10
seconds before the anti-theft alarm
indicator begins to flash. Subsequent closure of
the offending aperture will cause the alarm to
attempt full arming as previously described.
Immobilisation
The vehicle will be automatically immobilised
whenever any of the following conditions occur:
1.The vehicle is locked using the handset.
2.The vehicle is locked using the key.
3.Thirty seconds after the starter switch has been
turned off AND the driver's door opened.
4.Five minutes after the starter switch is turned off
or the alarm disarmed.

ELECTRICAL
9
DESCRIPTION AND OPERATION Mobilisation
The vehicle can be mobilised using any one of the
following processes:
1.Placing the handset in close proximity to the
starter switch with the starter switch turned on
(normally achieved by placing the key in the
starter switch, providing the key and handset are
attached).
NOTE: Under normal circumstances the
remobilisation of the vehicle will not be
apparent.
2.Pressing unlock button on handset.
3.Pressing lock button on handset with starter
switch turned on.
4.Entry of EKA code using the key.
NOTE: Any attempt to start the vehicle
using the key (detached from the handset)
will be unsuccessful. Use one of the above
methods.
See Warning indicators.
Volumetric protection
When the vehicle is locked using the handset both
perimetric and volumetric protection are activated
providing there is no mislock condition.
Perimetric protection
The vehicle is always perimetrically protected when
the alarm is armed using the handset. Perimetric
protection only, can be achieved if the vehicle is
locked using the key.
NOTE: The handset should ALWAYS be
used for unlocking the vehicle. If the
handset fails to unlock the vehicle
See
Repair, Handset.
Battery backed-up sounder (BBUS)
The sounder provides audible indication of alarm
status including:
Anti-theft warnings;
Confirmation of access to built-in test.
NOTE: Disconnecting the vehicle battery
will result in the alarm sounding if the
correct procedure has not been followed.
See Repair, Battery.
Alarm horn
The horn provides audible indication (as BBUS) of
alarm status.
NOTE: Disconnecting the vehicle battery
will have no effect on the horn.
Engine immobilisation warning light (EIWL)
NOTE: Under normal circumstances the
light will not illuminate.
The light will only illuminate (after 2 seconds) if the
handset is detached from the key (or the handset
fails) and an attempt is made to start the vehicle.
Anti-theft alarm indicator light
The light flashes to indicate the alarm status.
If the alarm system is fully armed, the light will flash
rapidly for 10 seconds and then settle to the slow
(anti-theft deterrent) flash.
If the alarm system is perimetrically armed, the light
will intermittently flash rapidly for 10 seconds and then
settle to the slow (anti-theft deterrent) flash.
If the alarm system is partially armed, the light will
NOT emit the slow flash until 10 seconds after arming
(to allow the cause to be investigated).
If the vehicle has been left unlocked, providing the
driver's door is closed, the light will flash slowly
indicating immobilisation. If the driver's door is open,
the light will remain illuminated.
Emergency key access (EKA)
The emergency key access code should be entered in
accordance with the instructions in the Owner's
Handbook.

ELECTRICAL
11
DESCRIPTION AND OPERATION ANTI-THEFT ALARM BUILT-IN TEST (96 MODELS)
NOTE: The handset should be detached
from the key to allow perimetric testing of
the alarm system. The system will
automatically switch to volumetric testing if the
handset is in close proximity to the starter switch.
The built-in test procedure can be accessed providing
the following conditions exist:
Alarm disarmed.
Ignition off.
Doors unlocked.
Bonnet[hood] closed.
The test mode can be entered by completing the
following instructions within 5 seconds:
1.Open bonnet.
2.Turn starter switch on.
3.Open driver's door (far enough to activate
switch).
4.Turn starter switch off.
5.Turn starter switch on.
If the test mode has been correctly accessed, the
sounder/horn will operate briefly and the anti-theft
alarm indicator and hazard warning lights will flash.
Perimetric tests
The anti-theft alarm indicator light and the hazard
warning lights will flash when:
1.Door switches are activated;
2.The bonnet is opened;
3.Sill switches are activated;
4.Key switches are activated.
NOTE: Operation of key switches can be
verified by turning the key in the relevent
direction so as not to simultaneously
activate the sill switch. If the key switch changes
state, the change should be detected but the sill
switch will not be activated.
Volumetric tests
Press the unlock button or move the handset close to
the starter switch to disable perimetric testing and
enable volumetric testing. If movement is detected
within the vehicle by the ultrasonic sensor it will be
indicated by flashing the anti-theft alarm indicator and
hazard warning lights.
NOTE: Exit anti-theft alarm built-in test by
turning starter switch to the off position.