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GF27.10-P-3029AHX Emergency-P Function




GF27.10-P-3029AHX Emergency-P Function
TRANSMISSION 722.930 up to 31.5.11, 722.931 as of 1.6.11
in MODEL 212.0/ 2

Function requirements for Emergency-P, general
^ Emergency motor supply voltage

Emergency-P, general
In emergencies, if for example undervoltage prevails in the on- board electrical system or the communication with the intelligent servo module for DIRECT SELECT (A80) is faulty, the emergency motor in the intelligent servo module for DIRECT SELECT is powered by the additional battery (G1/7) via the electronic ignition lock control unit (N73) and thereby triggers the emergency P function.

Function sequence for emergency-P
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
30 Main motor
31 Emergency motor
32/1 Left slide half
32/2 Right slide half
32/3 Coil spring
32/4 Release pin
33 Worm shaft
34 Eccentric shaft
35 Range selector lever
36 Angle sensor
40 Eccentric shaft position sensor
41 Drive pulleys
42 Drive belt

The additional battery supplies the emergency motor with voltage via the electronic ignition lock control unit in an emergency, e.g. in the event of undervoltage in the on-board electrical system.

This causes the eccentric shaft to turn.





Function sequence for intermediate position
30 Main motor
31 Emergency motor
32/1 Left slide half
32/2 Right slide half
32/3 Coil spring
32/4 Release pin
33 Worm shaft
34 Eccentric shaft
35 Range selector lever
36 Angle sensor
40 Eccentric shaft position sensor
41 Drive pulleys
42 Drive belt

The rotating eccentric shaft presses down onto the release studs of the left carriage half.
This in turn causes the mechanical connection between the left carriage half and right carriage half to be broken.





Function sequence for end position
30 Main motor
31 Emergency motor
32/1 Left slide half
32/2 Right slide half
32/3 Coil spring
32/4 Release pin
33 Worm shaft
34 Eccentric shaft
35 Range selector lever
36 Angle sensor
40 Eccentric shaft position sensor
41 Drive pulleys
42 Drive belt

The pre-compressed coil spring pushes the two slider halves apart.
The right carriage half slides along the threaded spindle to the right and pushes the range selector lever to position "P". The eccentric shaft rotates until the emergency motor is no longer actuated. The actual position of the eccentric shaft is detected by the eccentric shaft 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 drives the worm shaft by way of the drive belts. The left carriage half runs on to the right carriage half, the coil spring is pre-compressed again and the mechanical connection made again.

The Emergency-P function cannot be overridden manually.