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

GF27.10-P-0001AHC Automatic transmission (AT), function
- Transmission 722.902/904/906/908


Function description
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.

A minimization of the of the interfaces to the wiring loom is achieved by integrating the fully integrated transmission controller unit (Y3/8) in transmission 722.9. This improves the shift quality, increases the service life and reliability and also lowers maintenance costs.

Transmission 722.9 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 fully integrated transmission control controller unit with integrated fully integrated transmission control unit (Y3/8n4)

The fully integrated transmission control unit exchanges data with the following control units via the drive train CAN (CAN C):
- Electronic selector lever module control unit (/)N15/5
- CDI control unit (N3/9) (on diesel engines)
- ME-SFI [ME] control unit (N3/10) (on gasoline engines)

Data are exchanged with the following control units via the chassis CAN (CAN E) with the interface of the CDI control unit (with diesel engines) or ME-SFI control unit (with gasoline engines)
- Instrument cluster (A1)
- Electronic Stability Program control unit (N30/4) (except code (233) DISTRONIC PLUS)
- Electronic Stability Program Premium control unit (N30/7) (with code (233) DISTRONIC PLUS)
- Front SAM control unit with fuse and relay module (/)N10/1
- Electronic ignition lock control unit (N73)
- Steering column module control unit (N80)

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