Notes on 6-speed automatic gearbox 0AT — AUDI

Audi
Audi Q7
2007
Power transmission
Automatic gearbox 0AT, four-wheel drive
Edition
07.2006
Notes on 6-speed automatic gearbox 0AT
Design and function of gearbox
You can find out more about automatic gearboxes using the CD ROMs
Multimedia training; Power transmission parts 1 to 3
.
Gearbox
The 6-speed automatic gearbox 0AT, four-wheel drive has six hydraulically activated forward gears. When the lock-up clutch is closed these forward gears become mechanically driven gears by cutting out the torque converter slip.
Torque converter
The torque converter is equipped with a slip-controlled lock-up clutch.
Mechatronic unit
The mechatronic unit incorporates the hydraulic control system, the electronic
automatic gearbox control unit
J217
, the
multi-function switch
F125
and the sensors and actuators as a complete synchronised unit. The mechatronic unit is installed in the gearbox within the oil pan.
Control unit for automatic gearbox
J217
The control unit is part of the mechatronic unit in the gearbox.
The gear change point is calculated automatically (depends on driving situation and driving resistance).
Advantages:
Gear changes are timed for maximum fuel economy.
Maximum engine output is always available
Individual adaptation of gear change points in all driving situations
Gear change points are infinitely variable
Self-diagnosis
Before performing repairs to the automatic gearbox, determine the cause of the fault as precisely as possible using
“Guided fault finding”
.
“Guided fault finding”
is performed using the
vehicle diagnostic, testing and information system
VAS 5051 A
.
Variation of gear-change points for gradients
An additional gear change map automatically selects gear changes for gradients depending on 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
The engine braking effect can also be fully exploited via a specific gear, e.g. on gradients when towing a trailer, by directly selecting a gear with the tiptronic.