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

GF27.60-P-3012ACL Emergency default mode, function
- Transmission 722.618/646/694/696


Function requirements for limp-home mode, general
^ Circuit 87 ON
^ Circuit 61 ON

Limp-home mode, general
In order to guarantee a safe driving condition and in order to avoid damage to the transmission, the electronic transmission-control control unit (N15/3) switches to limp-home mode.

The fault is stored in the fault memory with the assigned fault code and the engine diagnosis indicator lamp (A1e58) in the instrument cluster (A1) is actuated.

In addition the fault is transmitted to the CDI control unit (N3/9) (with diesel engine) or ME-SFI control unit (N3/10) (with gasoline engine) via the drive train CAN (CAN C).

All solenoid valves and control solenoid valves are in the de energized condition:
^ Modulating pressure control solenoid valve (Y3/6y1)
^ Shift pressure control solenoid valve (Y3/6y2)
^ 1-2 and 4-5 gearshift solenoid valve (Y3/6y3)
^ 3-4 gearshift solenoid valve (Y3/6y4)
^ 2-3 gearshift solenoid valve (Y3/6y5)
^ Torque converter lockup clutch control solenoid valve (Y3/6y6)

The modulating pressure and shift pressure increase to the maximum value, the torque converter lockup clutch is shut off. The gear last engaged remains engaged.

After engaging gear range "P" it is possible to engage gear ranges "R" or "D".

In gear range "D", the transmission shifts to 2nd gear.

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

The faults stored in the fault memory can be read out using the DAS (DAS).