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GF27.10-P-0001AHZ Automatic Transmission (AT), Function



GF27.10-P-0001AHZ Automatic transmission (AT), 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]


Automatic transmission (AT). general
Transmission 722.9 is an electronically controlled automatic transmission with 7 forward gears and 2 reverse gears. The ratios for the gear stages are achieved by planetary gear sets. All the transmission functions and components for this transmission are combined in one assembly module.

The integration of the electric controller unit (VGS) (Y3/8) in the transmission means that the interfaces to the wiring harness have been minimized. This improves the shift quality, increases the service life and reliability and also lowers maintenance costs.

The transmission can be subdivided into the following assemblies:
- Torque converter with torsional damper and torque converter lockup clutch
- Oil pump for generating the necessary oil pressure and for reliable lubrication of the actuators and bearing points
- Transmission housing with mechanical transmission components (planetary gear sets, park pawl, multidisk clutches and multidisk brakes) and controller unit

Data is exchanged with the following control units via the engine compartment CAN (CAN-C):
- Instrument cluster (A1)
- Intelligent servo module DIRECT SELECT (A80)
- CDI control unit (N3/9) (on diesel engines)
- ME-SFI [ME] control unit (N3/10) (on gasoline engines)
- ESP control unit (N47-5)
- EIS [EZS] control unit (N73)
- Steering column module (N80)

Further partial functions are described in separate documents:
^ Transmission control, function
^ Key-P function
^ Gear shift, function
^ Power flow, function