System Functions

SYSTEM FUNCTIONS

Range Selection
The selector lever is connected to the transmission via a bowden cable, which operates the transmission selector shaft between all positions except Drive to 4.
The Transmission Control Module (TCM) detects the gear selected by means of a rotary position switch fitted to the transmission selector shaft. A separate Drive to 4 switch is located within the 'J' gate assembly.
Movement of the lever between Park, Reverse, Neutral and Drive manually controls the flow of transmission oil, the TCM having control of the forward gear selected in Drive.
Additional movement of the lever to 4, 3 and 2 positions does not manually modify the oil flow, the TCM detects these positions using the range switches and controls the gear electronically.

Shift Point Selection
The gearshift points are selected, by the TCM, as a function of the output speed, engine load, selector position and shift program selected. The driver has control over the shift points via the selector lever, throttle pedal movement, kickdown function and mode switch.

'J' Gate Layout:

Shift Map Selection
This is a software controlled feature where the TCM selects the most appropriate shift pattern in line with prevailing driving conditions.

Mode Switch
This switch allows driver selection of two base shift maps; Normal and Sport modes, the switch being illuminated when Sport is selected.

Special Shift Programs
These specific condition shift maps are available to enhance the operation of the vehicle under specific driving conditions. and are listed below in order of priority / title and operating condition, as follows:
1. Traction: When traction intervention is active.
2. Hot mode: Extreme engine / transmission temperatures.
3. Gradient: Under specific speeds and loads.
4. Cruise: During cruise control
5. Manual: Shift map when the LH side of the 'J gate' is used.
Three specific condition shift maps have a higher priority than the two base shift maps and will intervene when appropriate condition prevail for traction, cruise or gradient.
When traction control (engine or brake system derived) is operational the TCM will implement the traction map to maximise control of wheel slip.
The cruise map is intended to minimize unwanted gearshifts and 'hunting' and is activated when cruising near to the set speed, or resuming.
The gradient maps are intended to enhance vehicle drivability when towing or climbing a gradient. The TCM will implement the maps when increased driving resistance is detected and enhanced drivability, cooling and increased performance is appropriate.

Warm-up Function
The TCM will adopt a substitute shift pattern when the engine coolant temperature falls below a threshold. This 'warm-up' mode is intended to assist engine / catalyst warm-up, maximize economy and reduce emissions.