Mechanical backup with active control module

• The transmission shifts out of all forward gears into hydraulic 4th gear. The torque converter clutch is unlocked (not applied). All solenoid valves are de-energized.
• Maximum shift pressure is applied to the power-transmitting elements.
• Reverse gear can be engaged. The shift locksolenoid is active (in "P" and "N").
• All of the segments of the transmission range selector lever display are lit up completely.
  Fig 1: Identifying Transmission Range Selector Lever Display

  Courtesy of AUDI OF AMERICA, INC.
• The MIL lights up after 2 Dcy); check DTC memory (CHECK DTC MEMORY ) and compare with DIAGNOSTIC TROUBLE CODE (DTC) TABLE .

If the TCM -J217- malfunctions (e.g. if the power supply is faulty or the connector becomes disconnected), the transmission will immediately switch to "mechanical back-up mode with inactive control module" and continue to operate.