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

GF27.10-P-3029AHS Emergency-P function
- TRANSMISSION 722.9


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

Emergency-P, general
In emergencies, if e.g. 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 supplied with power from the on-board electrical system battery via the EIS [EZS] control unit (N73) (G1) and thus triggers the emergency-P function.

As of 1.9.08 with the eccentric shaft driven by the emergency motor the gearwheel drive is replaced by a belt drive.

Emergency-P function sequence
The function sequence is subdivided into the following steps:
^ Start position function sequence
^ Intermediate position function sequence
^ End position function sequence
^ Function sequence cancellation

Component Identification:

Start position function sequence
The emergency motor is supplied with power by the on-board electrical system battery via the EIS [EZS] control unit in an emergency, e.g. with undervoltage in the on-board electrical system, and turns the eccentric shaft.

Component Identification:

Intermediate position function sequence
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 and right carriage halves to be broken.

Component Identification:

End position function sequence
The pre-compressed coil spring pushes the two carriage 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 continues to rotate, until the emergency motor is no longer actuated. The actual position of the eccentric shaft is recorded by the eccentric shaft position sensor.

Function sequence cancellation
If undervoltage is no longer present in the on-board electrical system, the Emergency-P function is deactivated and the intelligent servo module for DIRECT SELECT reverts to its normal operating condition.

The main motor drives the threaded spindle by way of the drive pinion gears. 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.