Range Rover Classic. Manual - part 115

REAR SUSPENSION

SPECIFICATIONS, TORQUE

TORQUE VALUES

NOTE: Torque wrenches should be regularly checked for accuracy to ensure that all fixings are
tightened to the correct torque.

Anti-roll bar rear

- Strap nyloc nuts

..............................................................................

- Ball link self lock nut

........................................................................

- Castellated nut

................................................................................

Ball joint - levelling unit to rear axle

176

...........................................................

Top link bracket to rear cross member

......................................................

Levelling unit to cross member

..................................................................

Shock absorber to axle

..............................................................................

Torque values below are for all screws and bolts used except for those that are specified otherwise.

METRIC

......................................................................................................

.....................................................................................................

M10

...................................................................................................

M12

...................................................................................................

M14

105

..................................................................................................

M16

180

..................................................................................................

UNC / UNF

1/4

......................................................................................................

5/16

...................................................................................................

3/8

.....................................................................................................

7/16

...................................................................................................

1/2

.....................................................................................................

5/8

136

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AIR SUSPENSION

DESCRIPTION AND OPERATION

ELECTRONIC AIR SUSPENSION - (EAS)

Description

The electronic air suspension is a versatile
microprocessor controlled system that exploits the
advantages of air suspension. It provides a variable
spring rate which achieves near constant ride
frequency for all load conditions, giving:

•

Improved ride quality.

•

Continuity of ride quality, laden or unladen.

•

Constant ride height.

•

Improved headlamp levelling.

The function of the system is to provide five height
modes, each of which is automatically maintained at
the given height by the system logic with the minimum
of driver involvement. Vehicle height is sensed by four
rotary potentiometer type height sensors. Vehicle
height information from each potentiometer signals
the ECU to adjust each air spring by switching the
solenoid valves to hold, add or release air. The
system provides five height settings and automatic
self levelling as follows:

Standard - standard ride height measured from
centre of wheelarch eyebrow to floor = 790mm

7mm.

Low profile: 20 mm below standard.

Access: 60 mm below standard.

High profile: 40 mm above standard.

Extended profile: 20 to 30 mm above high profile.

Self levelling

The system provides self levelling under varying
vehicle loads. The vehicle will self level to the lowest
corner height level for 20 seconds after switching off
engine, exiting vehicle and closing doors.

Standard

Vehicle ride height is the same as with conventional
suspension, but is maintained under all load
conditions. This also provides improved headlamp
levelling.

Low profile

This position gives improved handling and fuel
consumption at high speed. When the vehicle speed
exceeds 80 kph (50 mph) for more than 30 seconds,
with INHIBIT switch off, the vehicle will enter the low
profile position. The vehicle will return to standard
height when vehicle speed drops below 56 kph (35
mph) for more than 30 seconds, unless vehicle stops,
in which case it returns to standard when driven away.
The LOWER lamp is illuminated in this condition.

Access

This position makes passenger boarding and luggage
loading easier. With the vehicle stationary, park brake
on (manual), ’P’ selected (automatic), footbrake off,
doors closed and INHIBIT switch off, pressing the
LOWER switch will select the ACCESS position. It is
possible to select access for 15 seconds after
switching engine off. The LOWER lamp flashes until
access position is reached, when it remain constantly
illuminated

NOTE: Opening a door will freeze vehicle
position.

From access the vehicle will return to standard ride
height if:
the RAISE switch is pressed,
or the INHIBIT switched is on,
or park brake is released,
or the is vehicle driven off.

High profile

This position is used to improve approach and
departure angles and when wading. Pressing the
RAISE switch will select this position provided the
road speed is below 56 kph (35 mph) with INHIBIT off.
The vehicle will return to standard position when road
speed exceeds 56 kph (35 mph) or LOWER switch is
pressed. The RAISE lamp is illuminated in this
condition.

NOTE: When raising ride height, rear of
vehicle will raise by 70% of movement first
followed by 70% of front. Rear will raise

remaining 30% before front. Lowering will be
achieved by lowering front of vehicle first. This
will ensure that, with headlamps illuminated, there
is no inconvenience from headlamp dazzle to
other road users. BUT, lowering to access
position will be achieved by the fastest possible
means, by opening all air valves at the same time.

AIR SUSPENSION

DESCRIPTION AND OPERATION

Extended profile

This position is achieved when vehicle is off road in
standard or high profile and the chassis is grounded
leaving wheels unsupported. Initial ECU reaction is to

deflate (lower) affected springs. After a timed period
ECU detects no height change, therefore it reinflates
springs in an attempt to regain traction. The RAISE
lamp will flash in this mode. After ten minutes system
will return to high profile, unless LOWER switch is
pressed.

LOCATION OF COMPONENTS

1. Electronic control unit (ECU) and relays.
2. Control switches
3. Compressor
4. Air drier
5. Valve block

6. Reservoir
7. Height sensors (4)
8. Front air spring (2)
9. Rear air spring (2)

10. Disable switch

AIR SUSPENSION

DESCRIPTION AND OPERATION

DESCRIPTION OF COMPONENTS

Electrical control unit - ECU

The ECU is located underneath the right hand front
seat, on top of the fuel ECU. It maintains the
requested vehicle ride height by adjusting the volume
of air in each air spring. It is connected to the cable
assembly by a 35 way connector. To ensure safe
operation the ECU has extensive on board diagnostic
and safety features. The ECU is non-serviceable, in
case of failure it must be replaced.

Relays, fuses

Power supply for the system consists of the following
components:

1. Delayed power turn off relay. This remains

powered up for 20 seconds after exiting vehicle
to allow self levelling.

2. Compressor relay, 4 pin.
3. Warning light relay, 5 pin.
4. 30 amp ’maxifuse’ for compressor power.

15 amp fuse in dash fusebox for ECU pin 1.

Disable switch

The disable switch is mounted on the RH runner
under the rear of the RH front seat. The switch has no
markings, in the DISABLE position the bottom of the
switch is pushed in. It is used to disable the system
when the vehicle is being delivered, or when working
on the system after depressurising. The switch
disables the system at speeds below 56 kph (35
mph).

Height sensors

Four potentiometer type height sensors signal vehicle
height information to the ECU. The potentiometers are
mounted on the chassis and activated by links to the
front radius arms and rear trailing links. In case of
height sensor failure the assembly must be replaced.

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