Description And Operation: Shifter
DESCRIPTION
The automatic transmission is operated with the help of a Shift Lever Assembly (Shift Lever Assembly) located in the floor console.
| 1 - Shift Lever Assembly |
- All selector lever positions, as well as selected shift ranges in position "D", are identified by the Shift Lever Assembly. The information is then sent to the Transmission Control Module (TCM) via a hard wire connection.
- There are four positions to which the selection lever can be shifted: P, R, N, D. In addition, the selector lever can be moved sideways (+/-) in position "D" to adjust the shift range.
1 - Shift Lever Assembly 2 - BTSI Override
OPERATION
The Shift Lever Assembly is comprised of the following functions:
- Park lock: The selector lever is not released from position "P" until the brake pedal has been applied and the ignition is in the "ON" position with the engine running. Shift lock is controlled by the brake light switch in conjunction with a locking solenoid in the Shift Lever Assembly. As soon as the brake pedal is applied firmly, the locking solenoid is energized and retracted to unlock the selector lever. If the selector lever cannot be moved out of position "P" due to a malfunction, the shift lock function can be overridden. Refer to MANUAL PARK RELEASE (MPR) - DISENGAGE AND ENGAGE .
- Reverse inhibitor: As soon as the vehicle speed exceeds approximately 6-11 km/h (4-7 mph), it is still possible to move the shift from position "N" to position "R", but the system will not shift into reverse until the vehicle speed has fallen below 7 mph. The reverse inhibit functionality is controlled by the same solenoid as the park lock. As the vehicle accelerates past the calibrated speed threshold, the solenoid is energized to block the sideways motion of the shift lever necessary to move from NEUTRAL to REVERSE. The reverse inhibit is not released until the vehicle speed falls below approximately 4-7 mph and the shifter is moved out of the "D" shifter position.
With the selector lever in position "D", the TCM automatically shifts the gears that are best-suited to the current operating situation. This means that shifting of gears is continuously adjusted to current driving and operating conditions in line with the selected shift range and the accelerator pedal position. Starting off is always performed in 1st gear.
The Shift Lever Assembly positions are determined by a sensor assembly internal to the Shift Lever Assembly. The sensor assembly identifies the various positions of the Shift Lever Assembly according to the following table.
| Shift Lever Assembly Position | Bit 0 | Bit 1 | Bit 2 | Bit 3 |
|---|---|---|---|---|
| Default | 0 | 0 | 0 | 0 |
| "D" | 1 | 0 | 1 | 0 |
| "N" | 0 | 1 | 1 | 0 |
| "R" | 1 | 1 | 1 | 0 |
| "P" | 0 | 0 | 0 | 1 |
| "+" | 1 | 0 | 0 | 1 |
| "-" | 0 | 1 | 0 | 1 |
| "ND" | 1 | 1 | 0 | 1 |
| "RN" | 0 | 0 | 1 | 1 |
| "PR" | 1 | 0 | 1 | 1 |
| Implausible | 1 | 1 | 1 | 1 |
The current Shift Lever Assembly position or, if the shift range has been limited, the current shift range is indicated in the instrument cluster display as well as the PRNDM.
The permissible shifter positions and transmission operating ranges are:
- P = Parking lock and engine starting.
- R = Reverse.
- N = Neutral and engine starting (no power is transmitted to the axles).
- D = The shift range includes all forward gears.
- M = Manual mode allows manual input of shifts up or down in all forward gears.