Procedure 1
Procedure: 11. Procedure and repair measures in the event of fault entries in the fault memory of the PDK control unit.
The required procedure for correcting faults for the groups of fault memory entries listed below is described using flow charts.
A separate flow chart is used for each of the fault groups specified below.
Information
You will find the flow charts under the heading "3730 - Flow charts for PDK fault codes" in the information medium TI - Technical Information releases, main group 3 - Transmission.
Sequence for correcting faults if various fault entries from various fault groups are present:
1) Electrical faults
2) Gear skip/engagement block
3) Sensor faults/software faults
4) Gear selection faults
Fault correction for complaints relating to comfort and noise must only be carried out after the faults listed above (if present) have been found and corrected.
1.1 Electrical faults
Electrical faults include all fault memory entries relating to fault type
^ Short circuit to ground
^ Short circuit to B+
^ Shunt
^ Open circuit
^ Incorrect voltage (operating limit, undervoltage, overvoltage).
Correct faults as shown in Flow chart EF - Electrical faults.
1.2 Gear skip/engagement block (fault memory entries P176x)
Gear skips/engagement blocks are identified by the fault memory entries 176x in the PDK control unit:
- P1764: Synchronization engagement blocks or gear skips
- P1768, P1769 and P176A ... to P176F: Synchronization fault (gear cannot be engaged)
- P1760: Double faults
Correct faults as shown in Flow chart EB - Gear skip/engagement block - P176x.
1.3 Sensor faults/software faults
"Sensor faults" include all fault memory entries relating to the components
- Distance sensor
- Speed sensor
- Pressure sensor
- Temperature sensor.
Correct faults as shown in Flow chart SF0 - SF5.
Overview of fault memory entries for distance sensor (Flow chart SF1)
- P1731 ... to P1734: Distance sensor information/shift rod faults (outside of validity range)
Overview of fault memory entries for speed sensor (Flow chart SF2)
- P0730: Transmission monitoring symptom - incorrect gear ratio
- P1743: Plausibility of transmission input shaft speed sensor clutch 1
- P1744: Plausibility of transmission input shaft speed sensor clutch 2
- P1745: Input shaft overspeed
Overview of fault memory entries for pressure sensor (Flow chart SF3)
- P0841 and P0846: Pressure sensor fault (measured value implausible)
- P17B1 and P17B2: Clutch fault (activation pressure implausible)
- P17B3 and P17B4: Clutch valve pressure stays too high mechanically during overlap switching after quick filling
- P17BB ... to P17BE: Clutch fault (clutch cannot be open)
Overview of fault memory entries for temperature sensor (Flow chart SF4)
- P0711: Transmission temperature sensor implausible
- P172D: Transmission temperature sensor gradient fault
- P17F0 to P17F2: Transmission overtemperature fault
Overview of fault memory entries for software faults (Flow chart SF5)
- P0602: Control unit not programmed
- P0603: EEPROM emulation checksum incorrect
- P0604: RAM test failed
- P0605: Flash checksum incorrect
- P0614: Data status does not match engine
- P0702: Watchdog (Monitoring Unit)
- P1749: Variant coding invalid
- P1870: Data record for shift rod synchronization invalid
- P1871: Data record for clutch synchronization invalid
- P1872: Data record for HYTI synchronization invalid (HYTI = Hydraulic Teach In).
- P1897: Software monitoring: Calculation of speed control intervention by engine implausible
- P174B: Invalid allocation of control unit and transmission hardware (cross-installation)
- P174C: BIN file does not match software version
- P174E: EEPROM content at system start incorrect/implausible
- P186F: Data record for electric synchronization data invalid
- P189A ... to P189D: Software monitoring
- P18A0 ... to P18B5: Software monitoring
- Uxxxx: CAN fault
1.4 Overview of fault memory entries for gear selection
- P17D0 ... to 17D9: Hydraulic gear selection fault
- P1779, P177A ... to P177F: Synchronization fault (gear cannot be disengaged) Other fault entries relating to the fault memory entries specified above that can be entered in the fault memory of the PDK control unit.
- P18B4: Software monitoring with fault type $24/$25/$26
- P1990, P1991: Engine torque intervention not possible (see also --> 373000 PDK transmission in limp-home mode: Fault codes P1552, P1990 and/or P1991 (77/09)) Correct faults as shown in Flow chart GS.