1995 LAND ROVER DISCOVERY ECO mode

75SUPPLEMENTARY RESTRAINT SYSTEM
2
DESCRIPTION AND OPERATION OPERATION
The airbag supplementary restraint system (SRS) is a
safety device which, when used in conjunction with
the seat belt, is designed to protect the driver and
front passenger.
Two different SRS systems are fitted to Discovery.
The Distributed SRS which has two crash sensors
located in the engine compartment on the chassis
longitudinals and the Single Point Sensing (SPS) SRS
which has a single crash sensor located in the Airbag
diagnostic control unit.
The change from distributed SRS to SPS SRS
occurred at VINs198222and528977.
Distributed SRS
In the event of a frontal impact, when the airbag
diagnostic control unit and one of the airbag crash
sensors senses the impact, the diagnostic control unit
fires igniters. This in turn ignites tablets of sodium
azide which generate a large amount of Nitrogen gas
leading to airbag inflation in approximately 30
milli-seconds.SPS SRS
In the event of a frontal impact, when the airbag
diagnostic control unit senses the impact, the
diagnostic control unit fires igniters. This in turn ignites
tablets of sodium azide which generate a large
amount of Nitrogen gas leading to airbag inflation in
approximately 30 milli-seconds.
All Models
When fully deployed the airbag offers additional
protection to the front seat occupant. As an occupant
moves into the airbag it immediately discharges the
gas to provide progressive occupant deceleration and
reduce risk of injuries. The whole process is
completed in approximately 0.3 seconds.
WARNING: All the airbag system
components, including the wiring harness,
MUST be renewed after the airbags have
deployed.

SUPPLEMENTARY RESTRAINT SYSTEM
3
DESCRIPTION AND OPERATION SRS warning light (airbag)
Distributed SRS
The warning light in the instrument pack illuminates
after the electrical circuits are switched on whilst a
system check is carried out. After about 8 seconds the
warning light will go out. The system checks airbag
diagnostic control unit, airbag crash sensors, airbag
harness, driver and passenger modules.
SPS SRS
The warning light in the instrument pack illuminates
after the electrical circuits are switched on whilst a
system check is carried out. After about 5 seconds the
warning light will go out. The system checks airbag
diagnostic control unit, airbag harness, driver and
passenger modules.
All Models
In the event of a fault in the system the warning light
will illuminate. The airbag diagnostic control unit logs
the fault which can only be accessed using TestBook.

CHASSIS AND BODY
45
REPAIR Refit
20.Position centre console assembly, ensuring
harnesses and connectors are not trapped and
are routed to their correct locations.
21.Connect cigar lighter multiplug and illumination
bulb Lucar.
22.Align centre console to body fixings and fascia.
23.Fit and tighten screws securing centre console to
body.
24.Lubricate hand brake lever to cable clevis pin.
25.Align hand brake cable to lever, fit clevis pin and
secure with clip.
26.Secure hand brake lever gaiter to centre
console.
Models fitted with electric front seats
27.Position electric front seat switches,connect
multiplugs and secure to centre console.
All models
28.Position centre console switch pack and connect
multiplugs to switches.
29.Align switch pack to centre console and secure
with screws.
30.Fit centre console switch pack cover.
31.Fit centre console rubber mat.
32.Fit gear selector lever knob and secure gaiter.
33.Fit transfer gear lever knob and secure gaiter.
34.Reconnect battery earth lead.DRINKS TRAY
Service repair no - 76.46.41
Remove
1.Disconnect battery negative lead.
2.Remove ash tray.
See ash tray - dash panel
central louvre panel.
3.Remove switch pack.See switch pack - dash
panel central louvre panel.
4.Remove 6 screws securing drinks tray to dash
panel central louvre panel.
5.Remove drinks tray.
Refit
6.Position drinks tray to dash panel central louvre
panel and secure with screws.
7.Fit switch pack.
See switch pack - dash panel
central louvre panel.
8.Fit ash tray.See ash tray - dash panel central
louvre panel.
9.Connect battery negative lead.

AIR CONDITIONING
3
REPAIR 5.Disconnect 2 pipe unions from oil cooler. Use a
second wrench to support hose adapter.
6.Remove transmission oil cooler. Seal
connections.
All models
7.Remove bolt securing receiver/drier clamp.
WARNING: Wear eye and hand protection
when disconnecting components
containing refrigerant. Plug all exposed
connections immediately.
8.Move receiver/drier just sufficiently to gain
access to pipe flange bolts without distorting the
pipes.
9.Remove bolt securing each pipe flange to
receiver/drier.
10.Disengage pipe flanges and withdraw
receiver/drier from mounting bracket.
11.Remove 'O' ring from each pipe flange.Refit
12.Fit new 'O' ring to each pipe flange, lubricate
with refrigerant oil.
13.Position receiver/drier in mounting bracket with
inlet and outlet connections correctly aligned.
14.Engage pipe flanges, fit bolts in turn and tighten.
15.Fit clamp bolt.
Automatic gearbox
16.Refit transmission oil cooler. Use a second
wrench to support pipe unions.
17.Check gearbox fluid level, top-up if necessary.
All models
18.Evacuate and recharge air conditioning system.
See Adjustment, Refrigerant Recovery
Recycling Recharging
19.Perform a leak test on disturbed joints.
20.Carry out a functional check.

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.

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
4
DESCRIPTION AND OPERATION BUILT IN TEST PROCEDURE
The built in test procedure is accessed as follows:
1.Starting conditions: ignition off, doors unlocked,
bonnet [hood] switch depressed.
2.Carry out instructions 3 to 7 within 8 seconds.
3.Release bonnet [hood] switch.
4.Switch ignition ON.
5.Lock doors.
6.Switch ignition OFF.
7.Switch ignition ON.
If alarm is correctly accessed, horn will sound and
LED will flash. The following checks can be made:
8.Open and close any door or tailgate - LED will
light.
9.Depress bonnet [hood] switch - hazards will
flash.
10.Check engine cranking is disabled. Do not turn
off ignition.
11.Check ultrasonic by operating handset, LED will
emit one 5 second flash, and will flash if interior
is disturbed.
NOTE: If ECU is new born mode any
handset of the right frequency will work. If
not an initialised handset is required see
Handset Initialisation.
12.Turn OFF ignition or press handset to end test
procedure. Horn will sound as before to indicate
end of test mode.

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.