General Information (6-Speed Automatic 09G)

6-speed automatic transmission DOG, general information
Comprehensive information on 6-speed automatic transmission is given in the self-study program.

Transmission
The 6-speed automatic transmission O9G is equipped with 6 hydraulically activated forward gears. The 2nd - 3rd - 4th - 5th and 6th gears become mechanically driven gears by cutting out torque converter slip when the lock-up clutch is closed.

Torque converter
The torque converter is equipped with a lock-up clutch. The lock-up clutch is closed dependent on load and speed. The 2nd, 3rd, 4th, 5th and 6th gears are then driven mechanically independent of slip.

ATF
The ATF oil is filled-for-life. The ATF does not require changing within the framework of a service.

When checking oil level use only ATF with the Part No. G 055 025 A2.

The ATF level in the planetary gearbox and the final drive is checked and filled simultaneously.

Guided fault finding, vehicle self-diagnosis and measuring technology.

Before performing repairs to the automatic transmission, determine the cause of the malfunction as precisely as possible with the aid of "Guided fault finding".

The guided fault finding is performed with Vehicle Diagnosis, Testing and Information System VAS 5051.

Transmission Control Module -J217-with driving situation gear changes (Fuzzy Logic)
Determining the driving situation and driving resistance dependent gear change point occurs automatically.
Advantages:
^ Gear changes are consumption orientated
^ Maximum engine output is always available
^ Individual adaptation of gear change points in all driving situations
^ Gear change points are infinitely variable

Gear change point variations for hills
An additional gear change map automatically selects gear changes for hills 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 braking effect of the engine