Land Rover Lesson 2 Auto Trans Coolingine Rover Manual

							Range Change Selection Switch
The range change selection switch in located behind the
main transmission selection lever, in the centre console.
The switch is a 3-position momentary action centre
sprung device. The driver pushes the lever forward to
select high range and back to select low range.
The switch comprises a housing, which provides the
location for a sliding contact. When the switch is moved
to the high or low position, it completes a momentary
connection to 12V with one of two micro-switches
located at each end of the range change selection switch.
These micro-switches correspond to the high or low
range positions.
The transfer box control module receives this
momentary signal and selects the requested range.
In this position, a spring will move the selector lever to
the centre position when released.
High/Low Position Sensor
The high/low position sensor converts the pivotal
movement of the high/low fork into a PWM signal on
the input. The PWM signal of the position sensor differs
between high range and low range. The control module
checks this signal and informs the driver, via the
instrument cluster and the range change selection switch
LEDs, if a range change is in progress or has been
completed.
The high/low position sensor is connected to the transfer
box control module via a three-pin connector.
TRANSFER BOX CONTROL
MODULE OUTPUTS
The transfer box control module sends the following
outputs:
•CAN bus messages
•Key interlock solenoid
•High/low range change LED
•Transfer box motor
•Solenoid.
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							CAN Bus Messages
The control module also sends messages via the CAN
bus to tell other control modules on the network, the
status of the transfer box. The high/low status, clutch
torque and default mode status are some of the main
signals sent out by the transfer box control module.
Key Interlock Solenoid
The transfer box control module is able to send a signal
to the key interlock solenoid. This signal locks the key
in the ignition barrel to prevent it from being removed
if the automatic transmission is not in the Park position.
High/Low Range Change LED
High range LED1
Low range LED2
The control module is responsible for illuminating the
2 high/low range change LEDs adjacent to the range
change lever. One LED indicates high range and the
other indicates low range.
One LED will be on continuously when in the
corresponding range.
When changing range, the current range LED will
remain on until the new range status has been achieved.
The new range LED will start flashing only when the
range change has commenced (i.e. speed and neutral
conditions have been met). The new range LED will be
illuminated continuously at the same instant that the
current range (now the old range) LED turns off.
The flash rate is 2 Hz with a 50% duty cycle.
The LEDs have 2 levels of intensity, high when the
vehicle lights are switch off and low when they are
switched on.
If both lights are flashing at 0.5 Hz, this would indicate
a transfer box fault or that the transfer box is in
undefined range and may require calibration.
Transfer Box Motor
The transfer box motor provides the necessary
movement to perform the high/low range change and
the multi-plate clutch actuation. The motor is located
on the rear casing assembly and secured with four bolts.
The motor is a PWM controlled, DC motor with an
integrated worm gear reduction drive. It is connected
to the transfer box control module with an eight-pin
connector; the power supply of the motor is maintained
through two large diameter cables on the motor
connector. An internal position sensor checks the
rotational movement of the motor.
There is an temperature sensor located within the motor
housing.
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							SolenoidThe solenoid switches the power flow on the actuation
system between high/low range change mode and clutch
control mode. When the solenoid is energized, the
solenoid pin deploys and activates the clutch control
mode. When the solenoid is de-energized, the internal
spring rejects the solenoid pin and activates the high/low
range change mode.
NOTE: In order to replace the solenoid in service, the
solenoid must be energized using the diagnostic tool.
The solenoid is connected to the transfer box control
module with a two-pin connector.
Status Indication
Instrument Cluster
High-line instrument clusterA
Low-line instrument clusterB
Low-range status indicator1
Message centre text (high-line only)2
Driveline fault lamp3
Driveline over temperature4
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							On vehicles fitted with the high line instrument cluster
there will be one low range status indicator. This
indicator will take the form of a mountain symbol and
has the following logic:
•Lamp on = low range
•Lamp off = high range
•Lamp flashing = range change in progress/range
undefined/range fault.
There will also be a message displayed in the message
centre, on vehicles with high-line instrument cluster,
which will inform the driver of any faults with the
transfer box.
The following table shows the messages that can be
displayed in the message centre of a high-line instrument
cluster relating to the transfer box:
ChimeDescriptionMessage
SingleTransfer case has engaged low range
after a range change request
LOW RANGE ENGAGED
SingleTransfer case has engaged high range
after a range change request
HIGH RANGE ENGAGED
SingleRange change request when vehicle
speed too high
SPEED TOO HIGH FOR RANGE
CHANGE
SingleRange change request when lever not
in neutral
SELECT NEUTRAL FOR RANGE
CHANGE
One per second for three secondsThis alerts the driver that the auto-
matic transmission park lock function
is inoperative due to transfer box out
of high or low range.
Transfer box control module has
stopped transmitting on the CAN bus
during a range change or while in
neutral mode and as a result the
automatic transmission park lock
function is inoperative
PARK LOCK FAILURE APPLY
HANDBRAKE (PARKBRAKE US/
CAN)
SingleTransfer box has detected a fault
inhibiting a new range change.
Control unit has shut down due to
thermal overload
RANGE CHANGE INOPERABLE
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							ChimeDescriptionMessage
SingleCentre differential temperature is
approaching the over heated
threshold
CENTRE DIFF OVER TEMP
REDUCE SPEED
SingleCentre differential has failed - oper-
ating as an open differential
CENTRE DIFF FAULT – TRAC-
TION REDUCED
SingleTransfer box control module has
stopped transmitting on the CAN bus
and defaults to open centre differen-
tial
CENTRE DIFF FAULT – TRAC-
TION REDUCED
The transfer box control module receives a gear position
signal from the manual transmission gear position sensor
and publishes the status on the CAN bus. This is
displayed in the odometer display, similar to how the
automatic transmission displays gear information.
DescriptionOdometer Display
Transmission is in neutralN
Transmission is in first gear1
Transmission is in second gear2
Transmission is in third gear3
Transmission is in forth gear4
Transmission is in fifth gear5
Transmission is in sixth gear6
Transmission is in reverse gear (Japan only)R
Transmission is between neutral and a gearBlank display
Transmission gear position sensor has a faultE
On vehicles fitted with the low line instrument cluster,
in place of the message centre there will be a status
lamp, which has the following logic:
•Amber - Over temperature
•Red - Failure, stop vehicle
The following table shows the faults that could possibly
illuminate the transfer box status lamp on vehicles fitted
with the low-line instrument cluster:
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							DescriptionIndication
Transfer box is operating at normal working temperatureOFF
Transfer box temperature is approaching the over heated
threshold
YELLOW WARNING LAMP ON
Transfer box has detected a fault, which affects the range
change function (current range is still maintained) or the
centre differential has failed to open.
YELLOW WARNING LAMP ON
Transfer box has detected a fault which renders the
transmission park lock function inoperative due to out
of range condition, OR centre differential has failed with
a non-zero locking torque
RED WARNING LAMP ON
Transfer box control module has stopped transmitting
on the CAN bus and defaults to open centre differential
YELLOW WARNING LAMP ON
Transfer box control module has stopped transmitting
on the CAN bus during a range change or while in neutral
mode and as a result the automatic transmission park
lock function is inoperative
RED WARNING LAMP ON
SERVICE
Basic Dimensions (Millimetres)
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							The transfer box weighs 40.30 kg without oil and 41.55
kg with oil. The unit requires 1500 ml ± 2% of oil from
empty.
The oil used in the transfer box is Shell TF 0753, which
has been specially developed by Magna Steyr and Shell.
The oil contains unique additives, which enhance the
transfer box operation. No other oil must be used in the
transfer box.
There is a unique type of grease, Weicon anti-seize
montagepaste grau TL 7391, that needs to be applied
the units input shaft spline when installing or reinstalling
the transfer box.
Input shaft spline1
DIAGNOSTICS
The transfer box control module can store fault codes,
which can be retrieved using T4 or a diagnostic tool
using KW2000* protocol.
The information is communicated via a diagnostic
socket.
The diagnostic socket allows the exchange of
information between the various control modules on the
bus systems and T4 or another suitable diagnostic tool.
The information is communicated to the socket via the
CAN bus. This allows the retrieval of diagnostic
information and programming of certain functions using
T4 or another suitable diagnostic tool.
The transfer box control module uses Diagnostic Trouble
Codes (DTC), which relate to transfer box electrical
faults.
Clutch and Range Change Mechanism
Calibration
In order for the range change mechanism to function
correctly, the transfer box control module must be
calibrated to the mechanical dimensions of the transfer
box that it is connected to.
This procedure will need to be followed if one of the
following occurs:
•The vehicle is first assembled
•The switch is changed
•The transfer box control module is changed
•The transfer box or range position sensor is changed
•Vehicle or transfer box control module fault has
caused the transfer box to revert to an undefined
range.
Calibration can be carried out using the service tool or
by following this procedure:
Switch ignition to position II without the engine
running
Select automatic or manual transmission neutral
Depress the throttle pedal fully
Press and hold the range change switch for 5 or more
seconds to allow calibration to start
When the calibration is heard to start, the switch and
throttle pedal can be released
Upon adopting high range, start the engine and wait
30 seconds while the first calibration of the clutch
in high range is done. While this calibration process
is in progress, no shifting is accepted
Switch ignition off and wait 15 seconds
Start engine
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							Perform a range change to low range. Wait 30
seconds while the first calibration of the clutch in
low range is done. While this calibration process is
in progress, no shifting is accepted
Switch ignition off and wait 15 seconds
Range and clutch calibration is now complete.
Manual Transmission Gear Learning Process
The transfer box control module must learn the
characteristics of the manual transmission to which it
is connected to be able to correctly recognise which
gear the driver has selected.
This procedure will need to be followed if one of the
following occurs:
The vehicle is first assembled
The switch is changed
The transfer box control module is changed
The manual transmission or gear position sensor is
changed.
The manual transmission calibration procedure can be
carried out in low or high range according to the
following process:
Start the engine
Drive the vehicle in reverse steadily for
approximately 5 seconds
Drive the vehicle forwards in all gears steadily,
spending a minimum of 5 seconds in each gear
•When driving in each gear it is important that the
clutch is fully released after a gear change so that
there is no clutch slipping during the learning
phase. The transfer box control module checks
clutch position during learning and will not learn
if the clutch is not fully released in each gear.
This is particularly relevant for reverse gear
where it is natural for drivers to slip the clutch.
Key off for 15 seconds to save learning
To check that the learning is completed key back on
and select a gear. The gear should be recognised
without the vehicle moving. T4 also shows if the
transmission learning has been completed.
SYSTEM OPERATION
The selection of high/low range is achieved by using a
switch located behind the main transmission selection
lever in the centre console. A range change can only be
performed when the transmission selector lever is in
neutral (position N for vehicles with automatic
transmission). The accelerator pedal must not be
depressed when a range change is in progress.
If high or low range is requested and the transmission
selector lever is in a position other than neutral, or N
or P, on vehicle with automatic transmission, the
instrument cluster message centre, if fitted, will display
SELECT NEUTRAL.
NOTE: On vehicles with automatic transmission, if the
transmission selector lever is in the P position, the
range change will not take place and the SELECT
NEUTRAL message will not be displayed in the
message centre.
When low range is selected, the low range mountain
symbol will flash when the range change is taking place
and then remain illuminated when the range change is
complete. The instrument cluster message centre, if
fitted, will display LOW RANGE for approximately
3 seconds followed by a chime from the instrument
cluster to confirm that the range change has been
completed. On vehicles with automatic transmission,
only D and Manual mode are available, the Sport
mode selection is not available.
When high range is selected, the low range mountain
symbol will flash when the range change is taking place
and then extinguish when the range change is complete.
The instrument cluster message centre, if fitted, will
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							display HIGH RANGE for approximately 3 seconds
followed by a chime from the instrument cluster to
confirm that the range change has been completed.
The design of the transfer box allows range changes
when the vehicle is moving, within set limitations as
follows:
•High to Low – at speeds not exceeding 25 mph (40
km/h) for vehicles with automatic transmission, and
12 mph (20 km/h) for vehicles with manual
transmission
•Low to High – at speeds not exceeding 37 mph (60
km/h).
If the vehicle speed is higher than the parameters given,
the instrument cluster message centre, if fitted, will
display SLOW DOWN. When the correct speed range
is reached, the message will be deleted and the range
change will commence.
The transfer box control module interprets a road speed
of less than 2 mph (3 km/h) as a static shift (vehicle not
moving). In this instance, on vehicles with automatic
transmission, the driver must use the shift lock
procedure of operating the brake pedal to allow the
selector lever to be moved from N to D after the range
change has been performed.
High range should be used for all normal road driving
and also for off-road driving across dry, level terrain.
Low range should only be required where low speed
manoeuvring is necessary, such as reversing a trailer,
negotiating steep slippery surfaces or boulder-strewn
terrain. Low range should also be used for extreme
off-road conditions where progress in high range cannot
be maintained. Low range should never be used for
normal road driving.
Terrain Response™
The Terrain Response™ system allows the driver to
select a program, which will provide the optimum
settings for traction and performance for the prevailing
terrain conditions.
The system is controlled by a rotary control located on
the centre console. The rotary control allows the
selection of one of the following five programs:
•Special programs off (general driving conditions)
•Grass/Gravel/Snow
•Mud/Ruts
•Sand
•Rock crawl.
The Terrain Response™ system uses a combination of
vehicle subsystems to achieve the required vehicle
characteristics for the terrain selected. The following
subsystems form the Terrain Response™ system:
•Engine management system
•Automatic transmission (if fitted)
•Transfer box
•Rear locking differential (if fitted)
•Brake system
•Air suspension.
Each subsystem control module provides a feedback
for the selected program so that the Terrain Response™
control module can check that all systems are controlling
the system correctly.
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							HIGH RANGE OPERATION
In high range, the torque input from the transmission is
passed to the transfer box input shaft. The position of
the synchroniser sleeve couples the shaft directly to the
differential housing. The differential splits the torque
between the two side gears. One side gear is connected
by splines and passes the torque to the rear output flange.
The second side gear is connected to the chain drive
sprocket and passes the torque, via the chain, to the front
output flange.
LOW RANGE OPERATION
In low range, the torque input from the transmission is
passed to the transfer box input shaft. The synchroniser
sleeve is moved and connects the planetary carrier to
the differential housing. The torque from the
transmission is now directed through the sun gear of the
epicyclic gearset and, via the pinion gears and pinion
gear shafts, into the planetary carrier. The annulus gear
of the epicyclic gearset is secured inside the casing and
generates the low range ratio of 2.93:1. The torque is
then passed, via the synchroniser sleeve, to the
differential housing where it is split between the two
side gears. One side gear is connected by splines and
passes the torque to the rear output flange. The second
side gear is connected to the chain drive sprocket and
passes the torque, via the chain, to the front output
flange.
HIGH/LOW RANGE GEARS WITH
SHIFT-ON-THE-MOVE
The driver is able to change between high and low range
gears while the vehicle is moving, or if the vehicle is
stationary.
Pushing the range change lever makes a range change
requests. This lever is located on the centre console
behind and to one side of the main transmission lever.
The driver requests a high to low range change by
pushing the range change lever towards the rear of the
vehicle and, conversely, a low to high request by
pushing the lever towards the front of the vehicle. The
range change lever is centre sprung and therefore does
not latch in the forward or rear positions.
The driver is informed of the range status via a green
lamp (mountain symbol) in the instrument cluster and
LEDs next to the range change lever. The lamp will not
be illuminated in high range, illuminated in low range
and flashing during a range change. There are two LEDs
on the range change lever one for high and one for low.
During a range change the new range LED will flash.
The vehicle will remain in the selected range unless the
driver requests a change, i.e. it will not automatically
revert to high range following a key off/key on
sequence.
RANGE CHANGE PROCEDURE
(AUTOMATIC VEHICLES ONLY)
Neutral must be selected on the main transmission
before requesting a range change and then select the
appropriate gear following completion of the range
change. During the range change the main transmission
will be locked in neutral.
If neutral is not selected when a range change is
requested then the request is denied and the driver will
be advised to select neutral via the instrument cluster
message centre (if fitted).
The range change process can take up to one second to
complete following a request being accepted.
There is a limit set on the maximum speed at which a
range change can be achieved. The maximum speed for
a high to low range change is 25 mph (40 km/h) for
vehicles with automatic transmission, and 12 mph (20
km/h) for vehicles with manual transmission. The
maximum speed for a low to high range change is 37
mph (60 km/h). If the vehicle speed is over the limit
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