| Pos. | spare part no | Name |
| 1 | - | TCM |
| 2 | - | neutral position "N" |
| 3 | - | 'Parking position "R" |
| 4 | - | Position sensor/mechanical shaft |
| 5 | - | electrical connector |
The TCM is located on top of the transmission case and is connected to a high speed CAN bus to communicate with other vehicle systems.
The TCM generates output signals to activate the transmission solenoid valves to control the hydraulic operation of the transmission.
Engine control data is sent to the ECM via a high speed CAN bus. To effectively control the TCM transmission, engine data such as crankshaft torque value, engine speed value, accelerator pedal angle, engine temperature, etc. are required.
The TCM processes signals from the transmission temperature and speed sensors, the ECM, and other vehicle systems. Based on the received signals and data stored in the memory, the module calculates the required gear, the torque converter clutch operating mode and the optimal pressure values for gear shifting and control of the torque converter lock-up clutch.
The steering angle sensor and ABS module also communicate to the TCM via the high speed CAN bus. The TCM uses this data to suspend shifting during cornering and also when the anti-lock braking system module (ABS) controls braking or traction control.
The TCM is located above a mechanical shaft that protrudes through an oil seal on the top surface of the main crankcase. The shaft is located in the rotation position sensor and turns the sensor in the desired direction on command from the gear selector lever. The rotation position sensor is a Hall effect sensor that outputs a certain voltage according to the selected selector lever position.
The selector lever is connected to the automatic transmission and rotation position sensor via a Bowden cable. The movement of the selector lever is transmitted via the Bowden cable to the position sensor, which reports the selected position (P, R, N or D) TCM. The sport/manual +/- switch is reported to the TCM via the LIN bus when the sport/manual mode selection has been made "CommandShift™". The TCM sends the relevant information on the high speed CAN bus to the instrument cluster, which displays the selected range information on the information center display.
If the TCM or transmission needs to be replaced, a setup procedure must be performed using the Land Rover approved diagnostic system so that the new TCM learns the neutral transmission position. The TCM uses the neutral position as a reference point for each of the P, R, N, and D positions.
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