Power Trunk Module

Inspection

System Parameterization
Parameterization of the system has to be performed to find the amount of pulses needed to open the trunk. Due to tolerances not every car is equal. Therefore the calibration is needed for each vehicle. Parameterization is started by pressing Trunk Inner switch and Trunk Outer switch at the same time for approx. 4 seconds. The trunk then will open until a blocking event is detected (normally full open position) and then close until it reaches the latch. During closing the HALL pulses are counted to know the travel distance. This value is stored into EEPROM.
This value has to be inside a defined tolerance to be considered as valid. If the value is outside of the tolerance parameterization was not completed successfully. Parameterization has to be done to find the full open position of a vehicle. It has to be done for each vehicle at least once. The sequence is started by pressing Trunk Inner switch and Trunk Outer switch at the same time. The trunk will then open until it is blocked. Then it will close until the latch reaches the power striker. During this closing the HALL pulses from the motor are counted. When the latch is closed the counter of the HALL pulses must have a value that is equal to a default value with a certain tolerance around it to complete the parameterization successfully. If the HALL pulse counter is outside the tolerance value the parameterization has not completed successfully. In case of a successful parameterization the new value for the full open position is stored into EEPROM.





System Initialization
System initialization is necessary to find the closed (0-Position) of the trunk-lid.
After Battery Power is on (Power-on stage) a initialization has to be done to find the closed trunk-lid position. After power-on the latch status is checked. If the latch is closed, it is assumed that the trunk lid is also closed. Therefore the trunk lid position is set to zero and initialization is finished. If the latch is opened it is assumed that the trunk lid is not closed. The power striker will be run into open position and the inner switch lamp will be switched on.
The next state is STOP. From this state the trunk can operate like in normal behavior - except the trunk lid speed is constant and the blocking margin is also constant (and higher than in normal operation).
After the trunk lid has reached the closed latch position, the initialization process is finished.
A blocking event in case of a not initialized trunk leads to state OPEN. During this operation the system is using the same default values like in the parameterization mode. The regulation and the blocking detection are active. The trunk can be opened / closed electrically or manually. However if the latch reaches the power striker the state is switched to LOCKED and the trunk status will be set to initialized.