General Information

General Information

Transmission

The 6-speed automatic transmission 0AT all-wheel drive is equipped with 6 hydraulically activated forward gears. When the lock-up clutch is closed these forward gears bypass the torque converter slip and become mechanically driven gears.

Torque converter

The torque converter is equipped with a slip-controlled torque converter lock-up clutch.

Mechatronic unit

The mechatronics unit incorporates the hydraulic control, the Transmission Control Module (TCM) (J217), the Multi-Function Transmission Range (TR) Switch (F125) and the sensors and actuators as a complete synchronized unit. The mechatronics unit is installed in the transmission within the oil pan.

Transmission Control Module (TCM) (J217)

The control module is a part of the mechatronics unit in the transmission.

Determining the driving situation and driving resistance dependent shift point occurs automatically.

Advantages:

• It is shifted depending on consumption;

• Maximum engine output is always available;

• Individual adaptation of shift points in all driving situations;

• Gear shift points are infinitely variable.

Self-diagnosis

Before performing service work on the automatic transmission, cause of damage must be exactly determined via "Guided Fault Finding".

"Guided Fault Finding" is performed using Vehicle Diagnosis, Testing and Information System (VAS 5051 A).

Gear change point variations for gradients

An additional gear change map automatically selects gear changes for gradients dependent upon accelerator pedal position and driving speed.

• Gear change map for extreme uphill stretches is matched to engine output

• Gear change map for extreme downhill stretches is matched to the braking effect of the engine

• Direct gear selection by way of the Tiptronic function permits utilization of engine braking action with a specific gear engaged, e.g. on a downhill gradient with a trailer