Reading And Writing Values

Information 

Information for replacing the transfer gear/servo motor. → WM 397855 REPLACING SERVO MOTOR ON TRANSFER GEAR (ALL MODELS) WM 397855 REPLACING TRANSFER GEAR CONTROL UNIT (ALL MODELS)  All-wheel drive control unit needs to be replaced: Missing offset and gradient values on the transfer gear (66/11)

• If the transfer gear with servo motor (control unit) is replaced, there is no need to reload data (classification data)  .
• Classification data can be read out of the control unit using the PIWIS Tester  .
• If only the servo motor is replaced, the classification data must be re-written into the control unit  .
• Classification data can be found on the transfer gear housing  .
  Fig 1: Locating Classification Data For Transfer Gear

  Courtesy of PORSCHE CARS NORTH AMERICA, INC.

→ Prior to disconnecting the control unit, switch off ignition and remove ignition key.

→ Ensure that the power supply is not interrupted during programming.

→ Connect a battery charger with a current rating of at least → Nominal value: 40 A  to the vehicle battery.

Information 

The PIWIS Tester II 9818  instructions take precedence since the description may be different with later Tester releases.

The procedure described here has been structured in general terms. Different text or additional information may appear in PIWIS Tester II 9818  .

1. PIWIS Tester must be connected to the vehicle before starting it. Switch on ignition.
2. Press [F12] to continue.
3. Select the required vehicle type.
4. Select the required control unit Transfer Gear  in the Overview  .
5. Maintenance/Repairs  must then be selected.
6. Control Unit Replacement  must now be selected. Then press [F12] to continue.
7. Read Data  must be selected. Then press [F12] to continue.
8. Press [F8] to start reading out data.
9. Check the chassis number and press [F12] to continue.
10. Switch off ignition and replace control unit. → 397819 REMOVING AND INSTALLING SERVO MOTOR ON TRANSFER GEAR .
11. Switch on ignition, select Write Data  in the menu (procedure described above), then press [F12] to continue.
12. Press [F8] to start. The data that was read out is installed.
13. The System Tester displays the message Data Has Been Written  . Press [F12] to continue.
14. Read out the fault memory and erase it if necessary.
15. Exit the menu and perform a test drive. Read out the fault memory for all control units after the test drive.

Information 

Information for replacing the transfer gear/servo motor. → WM 397855 REPLACING SERVO MOTOR ON TRANSFER GEAR (ALL MODELS) WM 397855 REPLACING TRANSFER GEAR CONTROL UNIT (ALL MODELS)  All-wheel drive control unit needs to be replaced: Missing offset and gradient values on the transfer gear (66/11)

• If the transfer gear with servo motor (control unit) is replaced, there is no need to reload data (classification data)  .
• Classification data can be read out of the control unit using the PIWIS Tester  .
• If only the servo motor is replaced, the classification data must be re-written into the control unit  .
• Classification data can be found on the transfer gear housing  .
  Fig 1: Locating Classification Data For Transfer Gear

  Courtesy of PORSCHE CARS NORTH AMERICA, INC.

→ Prior to disconnecting the control unit, switch off ignition and remove ignition key.

→ Ensure that the power supply is not interrupted during programming.

→ Connect a battery charger with a current rating of at least → Nominal value: 40 A  to the vehicle battery.

Information 

The PIWIS Tester II 9818  instructions take precedence since the description may be different with later Tester releases.

The procedure described here has been structured in general terms. Different text or additional information may appear in PIWIS Tester II 9818  .

1. PIWIS Tester must be connected to the vehicle before starting it. Switch on ignition and press [F12] to continue.
2. Select vehicle type.
3. Select the required Transfer gear  control unit in the overview  .
4. Select Maintenance/repairs  .
5. Select Control unit replacement  and press [F12].
6. Select Read data  and press [F12].
7. Press [F8] to start reading out data.
8. Check the chassis number and press [F12].
9. Switch off ignition and replace control unit. → 397819 REMOVING AND INSTALLING SERVO MOTOR ON TRANSFER CASE .
10. Switch on ignition. Select the Write data  menu (procedure described above), press [F12] and then press [F8] to start installing the data that was read out.
11. The System Tester displays the message Data has been written  . Press [F12] to continue.
12. Read out the fault memory and erase it if necessary.
13. Exit the menu and perform a test drive. Read out the fault memory for all control units after the test drive.