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GF27.60-P-3012GZ Emergency Default Mode, Function



GF27.60-P-3012GZ Emergency default mode, function
- Transmission 722.9


In order to ensure a safe driving state and to prevent damage to the automatic transmission, the electric controller unit (VGS) (Y3/8) switches to the limp-home mode if critical faults occur. In the event of a hardware fault all the control solenoid valves are switched off. They are then de-energized. In limp-home mode the transmission engages 6th gear. After gear selector switch position "P" is engaged, 2nd gear is engaged in gear selector switch position "D". On model 164.120/122/128/175/186 except code (430) off road package, reverse gear "R" is available with the ratio used for the deactivated off road program

On model 164.120/122/128/175/186 with code (430) off road package, on model 164.177 and on model 164.822/828/871/886 reverse gear "R" is available with the ratio used in the transmission mode "S".

As a result the vehicle can be brought to the nearest Mercedes-Benz service operation.

If hydraulic faults occur, the transmission does not shift out of the gear currently engaged. If the fault is in the control solenoid valves, the gear affected is locked out and cannot be engaged anymore.

In the fault memory up to 16 errors can be stored simultaneously. They can only be read out using STAR DIAGNOSIS.