Transmission Control Module (TCM) (2011-2012): Function: Shift-Lock
Shiftlock
To prevent the gear selector from accidentally being moved from P- or N-position, the vehicle also features an electrically operated lockout function (shiftlock). The shiftlock function unlocks the gear selector's lock in P-position and locks the shiftlock in N-position. In this way the gear selector is passively locked in P-position (inactive solenoid) and actively locked in N-position (active solenoid).
From P position to another gear position
In order to shift the gear selector from the P position to another gear position the ignition must be on and the brake pedal depressed (stop lamp switch activated). The transmission control module (TCM) retrieves the brake pedal position via the CAN network and the currently selected gear from the internal gear-shift position sensor. The signal is then transmitted from the transmission control module (TCM) to the gear selector module (GSM) to control the solenoid (electro magnet) in the gear selector assembly.
When the gear selector is in position P, the solenoid is activated and the lock pin slides in. The gear selector lock button can be pressed down as usual to select another gear. The Gear Selector Module (GSM) is in the gear selector assembly with a Hall sensor, which is affected by a permanent magnet
The Hall sensor is deactivated when the gear selector is moved from position P. The shift-lock solenoid is disengaged at the same time. This prevents the gear selector from sticking in position N. When the ignition is in position "I" or "0" the solenoid is deactivated. The gear selector is mechanically locked in position P by breaking the power supply to the solenoid.
From N position to another gear position
In order to shift the gear selector from the N position to another gear position the ignition must be on and the brake pedal depressed (stop lamp switch activated). The transmission control module (TCM) retrieves the brake pedal position via the CAN network and the currently selected gear from the internal gear-shift position sensor. The signal is then transmitted from the transmission control module (TCM) to the gear selector module (GSM) to control the solenoid (electro magnet) in the gear selector assembly.
With the gear selector in N, the solenoid is deactivated and unlocks the gear selector's interlock. One can then press the release button in the gear selector lever to engage D or M. The release button on the gear selector lever must be pressed to select R or P. The solenoid is deactivated when the ignition switch is in position "I" or "0".
Shiftlock override
In order to maneuver the gear selector assembly from P mode when its power is cut off or if there is an electrical fault, the lock mechanism in the gear selector assembly can be mechanically overridden. Under a cover on the gear selector assembly panel, a narrow tool can be inserted to release the gear selector.
The Transmission Control Module (TCM) has also an automatic shiftlock function (override) in order to control the gear selector to the locked P mode and from locked N mode in the event of an electrical fault.
Park / neutral position (PNP) function
The car has a park/neutral position (PNP) function to prevent the starter motor from turning when a gear is selected. This function is controlled by the transmission control module (TCM), which receives a signal from the gear selector module (GSM) indicating that the gear selector is in position P or N. The park / neutral position (PNP) function ensures that the starter motor can only be activated when the gear selector is in position P or N.