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GF27.10-P-3028AHZ Key-P Function



GF27.10-P-3028AHZ Key-P function
- Transmission 722.902/903/904/906/907 [model 164.1]
- Transmission 722.902/903/904 [model 164.8]
- Transmission 722.902/904/906/999 [model 251.1]


Key-P function requirements, general
^ Circuit 15 ON
^ Brake pedal operated
^ Vehicle speed greater than 8 km/h

Key-P, general
The designation Key-P comprises all the functions which in addition to the parking brake serve to secure the vehicle to prevent it from rolling away unintentionally.

Key-P function sequence
The function sequence is subdivided into the following steps:
^ Park pawl function sequence
^ Ignition lock lock function sequence
^ Selector lever position "P" lock function sequence
^ Emergency-P function sequence (see document, Emergency-P function)

Park pawl function sequence
The park pawl only permits shifting out of selector lever position "P" through the gear selector switch DIRECT SELECT (S16/13) when the transmitter key (A8/1) is turned into position "circuit 15 ON" and the brake pedal is operated.

In order to ensure that after parking the vehicle the selector lever is automatically shifted into selector lever position "P" by the intelligent servo module for DIRECT SELECT (A80), in this position the transmitter key can only be turned towards "0" and removed from the EIS [EZS] control unit (N73). The vehicle is secured mechanically by blocking the park pawl gear in the transmission.

With CODE (889) Keyless Go

On vehicles with Keyless Go, selector lever position "P" is engaged when the driver door is opened after the vehicle is parked.

Ignition lock lock function sequence
The EIS [EZS] control unit locks the transmitter key mechanically at a vehicle speed greater than 8 km/h.

It prevents the transmitter key from being removed because automatic engagement of selector lever position "P" cannot be performed by the intelligent servo module.

The transmitter key can be removed as long as the vehicle speed remains below the speed threshold and selector lever position "P" or "N" is automatically engaged by the intelligent servo module.

Selector lever position "P" lock function sequence
The selector lever remains locked in position "P" if the following conditions are not met:
- No power supply from intelligent servo module
- No enable signal from the drive authorization system (DAS 3)
- Brake pedal not actuated