Control Module HVAC: Testing and Inspection
WM 871125 Eliminating symptoms in body interior: Re-programming air-conditioning control unit (Cold ventilation air after starting engine/whistling noises from air-conditioning blower/SY2110)
Tools
Technical values
General information
Symptom
Information
These symptom-based repair instructions replace the instructions dated 15.09.2010.
Changes/additions compared to the previous instructions:
- Information changed under "Remedial action":
- Test software version 7.200.
- Information changed under "Re-programming air-conditioning control unit":
- Campaign number changed to SY2010FL02 in Step 4.3.
- After starting the engine, the heating/ventilation system in automatic mode (preset to medium and high temperature) can blow cold air (temperature of about 7 °Celsius) from the air vents in the vehicle for up to several minutes.
=> On right-hand drive vehicles
there can be a distinct temperature difference between the left and right side of the passenger compartment after starting the engine with the air conditioning set to automatic mode.
- In addition, whistling noises can come from the air-conditioning blower in certain air-conditioning system modes.
Cause, date of introduction and remedial action
Cause
Defective software for fan control.
Date of introduction
Vehicles produced since 30.07.2010 have updated software in the air-conditioning control unit.
Remedial action
Information
- Irrespective of the vehicle equipment, the air-conditioning system and steering wheel electronics control units will be re-programmed automatically when campaign number SY2010FL02 is selected.
- It is not possible to program the two control units individually.
Re-program the air-conditioning control unit using PIWIS Tester II with test software version 7.200 (or higher) installed.
Tools and materials
- PIWIS Tester II 9818 with test software version 7.200 (or higher) installed.
- Battery charger HFL 65 WE 1353 (charging current of at least 40 A).
Re-programming air-conditioning control unit
NOTICE
Programming interrupted
- Malfunctions in control unit
- Risk of damage to control unit
-> Before starting work, connect a suitable battery charger with a current rating of at least => Nominal value: 40 A to the jump-start terminals in the engine compartment.
-> For vehicles with Porsche Entry & Drive; Drive, remove the control panel from the ignition lock and instead of the control panel insert the original vehicle key into the ignition lock. Keep the control panel in a safe place.
-> Switch on the ignition using the original vehicle key for the duration of the work, otherwise the ignition will be switched off automatically after 10 minutes and control unit programming will be interrupted.
Information
The procedure described here is based on the PIWIS Tester II test software version 7.200.
The PIWIS Tester instructions take precedence and in the event of a discrepancy, these are the instructions that must be followed.
A discrepancy may arise with later software versions for example.
Information
If programming/coding is interrupted (e.g. due to a voltage drop or if communication is aborted, etc.) or if programming/coding could not be carried out successfully (error message "Programming/coding unsuccessful"), programming/coding must be repeated.
1. Connect PIWIS Tester II with installed test software version 7.200 (or higher) to the vehicle and switch it on.
2. Switch on the ignition using the original vehicle key.
3. Call up the => 'Diagnostics' menu and select the vehicle type => 'Cayenne'.
The diagnostic application starts.
4. Re-program the air-conditioning control unit:
4.1. In the => 'Control unit selection' menu, press F7 to call up the => 'Additional menu'.
4.2. Select => 'Campaign' and confirm your selection by pressing F12.
4.3. Click in the => 'Campaign number' input field and enter the following characters using the keyboard:
SY2010FL02
Press Enter on the keyboard to confirm your entry.
=> The input field turns blue.
4.4. Press F12 to continue.
4.5. Press F8 to start programming.
The message "Performing programming." appears at the top of the display.
Programming is carried out automatically by PIWIS Tester II and must not be interrupted.
When programming is complete, the message "Programming has been completed successfully" appears at the top of the display.
The progress bar at the bottom of the display shows 100%.
4.6. To finish programming:
Press F12 to continue.
4.7. Press F11 to return to the => 'Overview' menu.
5. Code the air-conditioning control unit:
5.1. Switch to the => 'Overview' menu, select "Air conditioning" control unit and press F12 to confirm your selection.
5.2. Switch to the => 'Codings/adaptations' menu, select the coding mode => "Automatic coding with coding rules" and confirm your selection by pressing F12.
Coding is performed.
The message "Coding has been completed successfully" appears at the top of the display.
5.3. Press F12 to continue.
6. Switch off ignition and wait for at least ten seconds.
7. Switch on the ignition again and restore communication between the PIWIS Tester and the vehicle.
8. Calibrate the steering-angle sensor (always required).
8.1. Select the control unit 'Steering wheel electronics' in the control unit overview (=> 'Overview' menu) and confirm your selection by pressing >>.
8.2. Once the 'Steering wheel electronics' control unit has been found and is displayed in the list, select the => 'Maintenance/repairs' menu in the menu bar.
8.3. Select the 'Steering-angle sensor calibration' function so that the corresponding text line turns blue and press >> to confirm your selection.
8.4. The functions for calibrating the steering-angle sensor that are not ticked must be carried out one after the other in accordance with the instructions on the PIWIS Tester.
To do this, select the relevant function so that it turns blue. Read and comply with the PIWIS Tester preconditions. This will involve turning the steering wheel to the left or right and then bringing the steering back to the centre again.
8.5. Once you have met the specified preconditions, press F8 ("Execute") to start the calibration process.
When calibration is completed successfully (message "Calibration has been completed successfully"), a tick will appear next to the function.
If the calibration process is not completed successfully, calibration must be repeated.
8.6. Once the steering-angle sensor has been calibrated fully (all functions are ticked), press << until you return to the start page of the 'Maintenance/repairs' menu.
8.7. Switch to the => 'Overview' menu and press << to return to the control unit overview.
9. Read and erase all fault memories.
9.1. Switch to the => 'Overview' menu and press F7 to call up the additional functions.
9.2. Select the function => 'Read all fault memories and erase if required' and confirm your selection by pressing F12.
The fault memories of the various control units are read out.
9.3. As soon as you have read out the fault memories, erase them by pressing F8.
9.4. Press F12 ("Yes") in response to the question as to whether you really want to delete all fault memory entries.
The faults stored in the fault memories of the various control units are deleted.
=> If control units are found to have faults, which cannot be erased and are not caused by control unit programming, these faults must be located and corrected.
9.5. Once you have erased the fault memories, select the => 'Overview' menu to return to the control unit selection screen.
10. Switch off ignition.
11. Switch off the PIWIS Tester and disconnect it from the vehicle.
12. Switch off the battery charger and disconnect it from the vehicle.
13. On vehicles with Porsche "Entry & Drive", replace the original vehicle key in the ignition lock with the control panel again.
Working time
87112540: Re-programming air-conditioning control unit; Labor time 50 TU