LR3/Disco 3
There are a number of different driving modes of operation. Some can be selected by the driver and some are
automatically initiated by the TCM during driving:
Normal mode
Sport mode
Manual (CommandShift™) mode
Adaptive Shift Strategy (ASIS)
Hill Descent Control (HDC) mode
Cruise mode
Hill mode
Default (Limp home) mode
Reverse lock-out mode
Cooling strategy.
Curve recognition mode
Fast off recognition
Normal Mode
Normal mode is automatically selected by the TCM on power up. In this mode all automatic and adaptive modes are
active. Normal mode uses gear shift and lock-up maps to allow for vehicle operation which offers fuel consumption and
emissions or driveability depending on the driving style. If the transmission is operated in sport or manual mode and the
selector lever is moved to the 'D' position, normal mode is automatically resumed.
Sport Mode
The sport mode operates in high range only and provides enhanced acceleration and responsiveness. In sport mode the
TCM uses shift maps which allow the transmission to downshift more readily, hold gears for longer at higher engine
speeds, and limits the transmission to the first five gears (6th gear is not used).
Sport mode is selected by moving the selector lever to the left into the 'M/S' position. When the sport mode is first
selected, 'SPORT' is displayed in the message centre for 6 seconds and, if 6th gear is currently engaged, the TCM
downshifts to 5th.
Manual (CommandShift™) Mode
Manual mode allows the transmission to operate as a semi-automatic 'CommandShift™' unit. The driver can change up
and down the six forward gears with the freedom of a manual transmission.
Shift maps are provided for manual mode to protect the engine at high engine speeds. The TCM will automatically change
up to a higher gear ratio to prevent engine overspeed and change down to a lower gear ratio to avoid engine labouring
and stalling.
When kickdown is requested the TCM downshifts at least 2 gears.
When the vehicle is stationary, to drive off the driver can select 1st , 2nd or 3rd gear in low and high range. Any other
gear selection will be rejected by the TCM.
When driving off, upshifts can be pre-selected by making + selections with the selector lever for the number of upshifts
required. The TCM then automatically performs a corresponding number of upshifts when the appropriate shift points are
reached. So, for example, when starting off in 1st gear, if three + selections are made in quick succession, the TCM will
automatically change up through the box to 4th gear as the vehicle accelerates, without any further selections being
made.
In manual mode a low gear can be selected to provide engine braking for descending a slope without HDC or continuous
use of the brake pedal. The driver can prepare for the end of the descent by moving the selector lever to D. The TCM will
maintain the low gear and only revert to automatic shift control when the throttle is opened and vehicle speed increases.
Adaptive Shift Strategy (ASIS)
The ASIS system is a new feature on automatic transmissions. With the TCM linked via the CAN bus to other vehicle
systems, signals are received which can allow the TCM to calculate the way in which the vehicle is being driven. The type
of signals include the following:
