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

GF27.10-P-0001AHL Automatic Transmission (AT), Function
- TRANSMISSION 722.9 (except 722.930 /931) in MODEL 212

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.

Integrating the fully integrated transmission control controller unit (Y3/8) in the transmission minimizes the number of interfaces to the wiring harness.

Production breakpoints for implementation of fuel-efficient and comfort-enhancing measures on automatic transmission

- Model 212.0/2 with engine 272 and 273 as of 07/2010
- Model 212.0/2 with engine 276 and 278 as of 06/2011
- Model 212.0/2 with engine 271.8 from 03/2011
- Model 212.0/2 with engine 642.8 from 07/2010
- Model 212.0/2 with engine 651.9 as of 12/2010

Depending on the model, fuel-efficient and comfort-enhancing measures may be implemented at a later date.

Fuel-efficient and comfort-enhancing measures for the automatic transmission

Service life can be increased, fuel consumption reduced, gearshift comfort improved and maintenance intervals revised by using optimized transmission components and a new automatic transmission fluid and by reducing working pressure and implementing software modifications

The transmission can be subdivided into the following assemblies:
- Torque converter with torsional damper and torque converter lockup clutch
- Torque converter with integral centrifugal pendulum and torque converter lockup clutch (278.9, 642.8 and 651.9)
- Oil pump for generating the necessary oil pressure and for reliable lubrication of the actuators and bearing points
- Electrical transmission oil pump (M42) (with code (B03) ECO start/stop function) for generating required oil pressure and for reliable lubrication of the actuators and bearing points at engine OFF
- Transmission housing with mechanical transmission components (planetary gear sets, parking lock, multidisk clutches and multidisk brakes) and fully integrated transmission control controller unit

Data is exchanged with the following control units via the drive train CAN (CAN C):
- DIRECT SELECT intelligent servo module (A80)
- CDI control unit (N3/9) (on diesel engines)
- ME-SFI [ME] control unit (N3/10) (on gasoline engines)
- Transmission oil auxiliary pump control unit(N89) (with code (B03) ECO start/stop function)

Data is exchanged with the following control units via the chassis CAN (CAN E) with the interface of the CDI or motor electronics control units:
- Instrument cluster (A1)
- Electronic stability program control unit (N30/4) or Premium electronic stability program control unit (for code (233) DISTRONIC PLUS) (N30/7)
- Front SAM control unit with fuse and relay module (N10/1)
- Electronic ignition lock control unit (N73)
- Steering column module control unit (N80)

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