Emergency-P Function - GF27.10-P-3029AHE
TRANSMISSION 722.9 (except 722.930) in MODEL 205
Function requirements for Emergency-P, general
- Emergency motor supply voltage
Emergency-P, general
In emergencies, for example if undervoltage prevails in the on-board electrical system or communication with the intelligent servo module for DIRECT SELECT (A80) is faulty, the emergency motor (31) in the intelligent servo module for DIRECT SELECT is supplied with power from the on-board electrical system battery (G1) via the electronic ignition lock control unit (N73) with the interface of the powertrain control unit (N127) and thus triggers the Emergency-P function.
Emergency-P function sequence
The function sequence is described in the following steps:
- Function sequence for start position
- Function sequence for intermediate position
- Function sequence for end position
- Function sequence for cancellation
Function sequence for start position
The emergency motor (31) is supplied with power by the on-board electrical system battery via the electronic ignition lock control unit with the interface of the powertrain control unit in case of emergency, e.g. in the event of undervoltage in the on-board electrical system, and turns the eccentric shaft (34).
Function sequence for intermediate position
The rotating eccentric shaft (34) presses on the release pin (32/4) of the left carriage half (32/1).
This in turn breaks the mechanical connection between the left carriage half (32/1) and the right carriage half (32/2).
Function sequence for end position
The pre-compressed coil spring (32/3) pushes the two carriage halves apart. The right carriage half (32/2) slides along the lead screw (33) to the right and pushes the range selector lever (35) to position "P". The eccentric shaft (34) rotates until the emergency motor (31) is no longer actuated. The actual position of the eccentric shaft (34) is detected by the eccentric shaft (40) position sensor and passed on to the electronics of the intelligent servo module for DIRECT SELECT.
Function sequence for cancellation
The emergency P-function is automatically overridden, if the emergency case, which, e.g. is caused by undervoltage in the on-board electrical system, is no longer given. The main motor (30) rotates the worm shaft (33) by way of the drive belt (42). The left carriage half (32/1) runs on to the right carriage half (32/2), the coil spring (32/3) is pre-compressed again and the mechanical connection is restored.
The Emergency-P function cannot be overridden manually.
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