- Normal mode
- Sports mode
- Manual CommandShift™
- Cooling
- Descent control system (HDC)
- Moving at a constant speed
- Emergency mode
- Inertia
- Recognition of a sudden rejection of a decision
- Driving uphill and transporting a trailer
- Downhill driving
- Wide open throttle
- Terrain Response System
- Reverse lock mode
Normal mode
Normal mode is automatically selected by the TCM when the ignition is turned on. This mode is fully automatic and has an adaptation function. Normal mode uses shift and torque converter clutch programs to provide optimal fuel consumption, emissions and handling characteristics depending on the vehicle's driving style.
If the transmission is in Sport or Manual CommandShift™ mode and the selector lever is moved to the "D", the normal mode resumes.
Sports mode
Sport mode provides better acceleration and responsiveness through the use of sport shift programs. This mode allows you to downshift faster and spin the engine in one gear to higher rpm.
Manual CommandShift™
CommandShift manual mode allows the gearbox to operate in semi-automatic mode. The driver can shift 6 forward gears in any direction as easily as in a manual transmission.
Shift programs provide engine protection at high engine speeds. The TCM will automatically upshift to protect the engine from over-revving and downshift to avoid overloading the engine and preventing it from stalling under load.
Upon receipt of a request to enable the mode "kick-down" The TCM shifts down to the lowest available gear. The driver can select 1st, 2nd or 3rd gear to start the car.
Through repeated (according to the number of the overdrive to which you want to change) shifting the selector lever to position "+" it is possible to pre-program a shift to a higher gear when starting off. The TCM then performs the requested upshifts when the appropriate shift schedule points are reached. For example, if before starting off in 1st gear 3 times in a row, quickly move the selector lever to the position "+", the TCM will automatically shift to 4th gear as it picks up speed without further intervention.
Cooling
Cool mode is activated when the TCM detects an excessively high transmission fluid or engine coolant temperature. In this mode, the torque converter lock-up is engaged earlier to minimize further increase in transmission fluid and/or engine coolant temperature and to assist in cooling the transmission fluid.
Descent control system (HDC)
The HDC mode helps the ABS module to regulate the speed when going downhill. When the HDC system is engaged, the TCM selects the most suitable gear for the most effective engine braking.
Maximum engine braking is achieved by using a shift program that initiates later upshifts and earlier downshifts.
Moving at a constant speed
When the speed control system is enabled, the TCM receives a message on the high speed CAN bus that the speed control system is being activated (cruise control). The TCM activates a speed control program that minimizes up and down shifts.
Constant speed drive mode is active when the speed control system is activated and the transmission is in drive mode "D", in sport mode "S", in HDC mode or in Terrain Response Grass/gravel/snow mode (program «Grass/gravel/snow»). Unique constant speed drive programs replace the current mode and provide a smooth ride feel and smooth mode reselection.
Emergency mode
If a malfunction is detected in the transmission, the TCM selects emergency control mode and the information center display shows the message "TRANSMISSION FAULT LIMITED GEARS AVAILABLE" (transmission failure, limited number of gears available). If a fault occurs that affects exhaust emissions, the MIL warning lamp on the instrument panel comes on.
In emergency mode, you can normally use the positions P, R and N (unless a malfunction occurs), and to continue driving to the nearest Land Rover dealer or approved repair shop, the TCM locks the transmission in 3rd gear. The torque converter lock-up is disengaged and the reverse gear lock does not work.
If the vehicle in limp home is stopped and then restarted, the TCM will use normal mode until the next fault that caused the limp home is detected.
Inertia
Coasting mode (coasting) provides earlier downshift during coasting, depending on the degree of deceleration of the output shaft; this is to improve handling and smoothness characteristics by avoiding negative or positive transmission torque reversal during downshifts.
Recognition of a sudden rejection of a decision
When the driver abruptly releases the accelerator pedal, the TCM interprets this as a rejection of the previously made decision. The TCM recognizes that the decision has been rejected by a high accelerator pedal up signal from the ECM on the high speed CAN bus. When this situation occurs, the TCM maintains the current gear to allow the driver to complete the maneuver without downshifting. This state is maintained for a preset period of time or for a period of driver inactivity.
The sudden reversal detection mode promotes vehicle stability and is used in conjunction with the lateral acceleration input during cornering to maintain the current gear until the corner is passed.
Driving uphill and transporting a trailer
Hill and trailer mode can be active when the transmission is in Normal, Sport or Terrain Response mode. When the vehicle is pulling a trailer or climbing a hill, the TCM detects increased resistance by monitoring engine torque and engine speed signals from the ECM on the high speed CAN bus, as well as transmission output speed sensor signals. The uphill and trailer mode provides low gear shifting to prevent drop in transmission output torque and maintain driving force.
Downhill driving
The downhill mode can be active if the transmission is in Normal, Sport or Terrain Response mode. When the vehicle is going downhill, the TCM detects a decrease in resistance by monitoring the engine torque and engine speed signals transmitted by the ECM over the high speed CAN bus, as well as the transmission output speed sensor signals. Downhill driving assists engine braking by selecting the appropriate gear to reduce the load on the brakes.
Wide open throttle
Wide-open throttle mode controls shifting to high gears at part-throttle and in "kick-down". This ensures a constant wide-open throttle setting under all driving conditions. The full range of engine speeds is used in all driving modes: normal, sport, uphill, downhill and Commandshift. For delays (hydraulic and electronic) The gear change request uses compensation to ensure a smooth gear change and correct shift point correction.
Terrain Response System
The Terrain Response system has a unique set of shift programs for each Terrain Response program. These programs override the current modes, for example, if a program is selected while HDC mode is active "Sand" ("Sand"), "Mud and Ruts" ("Mud and ruts") or "Grass/Gravel/Snow" ("Grass/gravel/snow"), then the specific Terrain Response switching program is used in this case, and not the HDC mode switching program described earlier.
Reverse lock mode
If the selector lever is moved from position N to position R and the vehicle is moving forward, reverse gear selection is prevented at a vehicle speed of 11 km/h (6.8 mph) or more. When the reverse gear lock is in operation, the clutch is released (C3) without power supply to the solenoid valve (SLC3), which prevents the gearbox from selecting reverse gear.
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