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Key-P function - GF27.10-P-3028ACS

TRANSMISSION 722.649 in MODEL 216.3 as of Model Year 09 /YoM 08 

TRANSMISSION 722.649 in MODEL 221.1 as of Model Year 09 /YoM 08 

Key-P function requirements, general 

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 

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.

IMPORTANT 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 function sequence 

The EIS [EZS] control unit locks the transmitter key mechanically at a vehicle speed >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:

REFER TO SYSTEM WIRING DIAGRAMS electrical function schematic Key-P Model 216 PE27.19-P-2058-97CAA
    Model 221 PE27.19-P-2058-97SAB
  Emergency-P function   GF27.10-P-3029ACS 
  Intelligent servo module for DIRECT SELECT, component description A80 GF27.19-P-4020ACS