When moving from a standstill, upshifts can be pre-selected by making '+' selections with the selector lever for the
number of upshifts required. The TCM then performs the requested number of upshifts when appropriate shift points are
reached. For example; when moving off in 1st gear, if 3 '+' selections are made in quick succession, the TCM will
automatically upshift through the gears to 4th gear as the vehicle accelerates, without any further selections being made.
Cooling
Cooling mode is activated when the TCM detects excessively high transmission fluid or engine coolant temperatures. When
this mode is active torque converter lock-up is activated earlier to minimize a further rise in fluid and/or engine coolant
temperature and assist fluid cooling.
Hill Descent Control (HDC)
The HDC mode assists the ABS module in controlling the downhill speed of the vehicle. When HDC is active, the TCM
selects the most appropriate gear for the descent to maximize engine braking.
Maximum engine braking is applied using a shift map which initiates later upshifts and early downshifts.
Cruise
When speed control is activated, the TCM receives a speed control active message on the high speed CAN bus. The TCM
activates a speed control map which minimizes up and down shifts.
Cruise mode is active when speed control is selected on and the transmission is in drive 'D', sport 'S', HDC or Terrain
Response Grass/gravel/snow program. Unique cruise maps override the current mode to provide a smooth driving feel and
mode reselection.
Limp Home
If a transmission fault is detected by the TCM, the TCM adopts a limp home strategy and a message 'TRANSMISSION
FAULT LIMITED GEARS AVAILABLE' is displayed in the message center. If the fault has an effect on engine emissions, the
MIL in the instrument cluster will also be illuminated.
In limp home mode, P, R and N functions operate normally (if the fault allows these selections) and the TCM locks the
transmission in 3rd gear to allow the driver to take the vehicle to a Land Rover dealer or approved repairer. Torque
converter lock-up is disabled and reverse-lock-out will not function.
If the vehicle is stopped and subsequently restarted in the limp home mode condition, the TCM operates normally until the
fault which caused the condition is detected again.
Coast
Coast mode provides earlier downshifts during coasting dependant on output shaft deceleration rate to improve driveability
and refinement by avoiding negative to positive driveline torque reversals transmission during the downshifts.
Fast Off Recognition
Fast off recognition is activated when the TCM detects that the driver has released the accelerator pedal quickly. This is
detected by the TCM monitoring for a high level of negative pedal angle from ECM signals on the high speed CAN bus. If
this condition is detected, the TCM holds the current gear ratio to allow the driver to complete the manoeuvre without the
need for a downshift. The mode can remain active for a predetermined length of time or if the driving style remains
passive.
Fast off recognition mode assists vehicle stability and is used in conjunction a lateral acceleration input during cornering to
maintain the current gear until the corner is negotiated.
Uphill and Trailer
Uphill and trailer mode can be active when the transmission is operating in normal, sport or Terrain Response modes.
When the vehicle is pulling a trailer or driving up an incline, the TCM detects the increased resistance by monitoring engine
torque and speed signals received from the ECM on the high speed CAN bus and also transmission output shaft speed
sensor signals. Uphill and trailer mode will provide downshifts to prevent a drop in transmission torque output and
maintain driving force.
Downhill
Downhill mode can be active when the transmission is operating in normal, sport or Terrain Response modes. When the
vehicle is descending an incline the TCM detects a reduction in resistance by monitoring engine torque and speed signals
received from the ECM on the high speed CAN bus and also transmission output shaft speed sensor signals. Downhill mode
assists engine braking by selecting an appropriate gear reducing the load required on the brakes.
Wide Throttle
Wide open throttle mode operates for part throttle upshifts and kick-down upshifts. It provides consistent wide open
throttle upshift performance under all driving conditions. The full engine speed range is used in all driving modes; normal,
sport, hill modes and Commandshift. Compensation is used for delays (hydraulic and electronic) in gear change request to
gear change start to provide smooth changes and correct shift point correction.
Terrain Response
The Terrain Response system has a unique set of shift maps for each of the Terrain Response programs. These programs
override existing modes; for example when HDC is active and the 'Sand', 'Mud and Ruts' or 'Grass/Gravel/Snow' programs
are selected, a specific Terrain Response map is used, not the HDC mode shift map detailed previously.