Pressure Regulator 4 (System Pressure), Open Circuit

P2721

Diagnosis information - PDK

Pressure regulator 4 (system pressure), open circuit

Diagnostic conditions
The control unit initially tests internal function sequences when the ignition is switched on (terminal 15). If they are OK, all diagnosable outputs are then tested and any faults are stored.

- Ignition on
- The following fault is not detected: P1832
- The following fault is not detected: P183A
- Pressure regulator 4 active

Possible fault causes
- Line between pressure regulator 4 and PDK control unit faulty
- Pressure regulator 4 faulty
- PDK control unit faulty

Fault setting conditions
- Internal current measurement, pressure regulator 4: current consumption = 0 mA
- Line resistance between pressure regulator 4 and PDK control unit > 1 MOhm

Fault effects
- System pressure control switch-off
- Pressure regulator 4 switch-off
- Engaged gear is held until vehicle stops.
- Moving off possible only in 2nd gear
- Transmission limp-home indication in instrument cluster control unit