Drivetrain - '4WD' System Faulty Message/DTC 2039
Cayenne8/04 3965
Date: 2-9-05
Binder - 3, Power Transmission
Warning Message in Instrument Cluster:
4-Wheel Drive System Faulty
Vehicle Type:
Cayenne/Cayenne S/Cayenne Turbo
Model Year:
As of '03 (3)
Concerns:
Servo motor in transfer box may cause:
- Warning in instrument cluster: "4-wheel drive system faulty",
- Fault code 2039 stored in transfer box control unit memory.
Information:
The following instructions provide information about the procedure and measures to be taken in connection with the "4-wheel drive system faulty" warning message. A customer's statement and the PIWIS Tester (software version 5.0 or higher) are required for the evaluation in order to carry out the diagnosis.
Reports (= customer's statement or fault-memory logs) must be prepared during the procedure.
Please number these reports according to the notes in the procedure description (= report No.). This will improve assignment and evaluation of the fault.
If it becomes necessary to replace the servo motor during the course of the diagnosis, the servo motor should be returned to the Atlanta Warranty Test Center using normal return procedures. The component must be accompanied by the warranty processing bar code and the prepared reports (= customer's statement, fault memory logs).
Work Procedure:
1. Customer's statement (report).
1.1 When the customer brings in the vehicle with a complaint, the customer needs to describe in detail which driving situation and which external circumstances activated the "4-wheel drive system faulty" warning message in the instrument cluster.
The customer's statements should be based upon the following criteria and include (-- report No. 1/1.1) as a keyword:
^ Driving program: on-road program (High Range) or off-road program (Low Range)?
^ For Low Range use:
- in automatic mode (= rocker switch pressed once/1 LED lit on the display) and/or
- with fully engaged center differential lock (= rocker switch pressed twice/2 LEDs lit)
^ When driving uphill, downhill or on level ground?
^ When driving through bends or straight ahead?
^ During acceleration or deceleration of the vehicle?
^ When/after the engine is started or after which length of driving time (approx.)?
^ Outside temperature (approx. temperature to the nearest 40° F (5° C), 50° F. (10° C), etc.
^ Was the warning message sporadic (= not displayed in the instrument cluster after the next start of the engine) or static (= permanently displayed even after the engine is started again)?
^ Which rocker-switch LEDs flashed or were permanently lit?
2. Diagnosis.
2.1 Connect PIWIS Tester and switch on ignition and PIWIS Tester. Start diagnosis.
2.2 Select transfer box control unit and read out fault memory.
2.3 Print out fault memory log (report No. 2/2.3).
2.4 Erase fault memory, end diagnosis and switch off ignition.
2.5 Switch the ignition on and start diagnosis again.
2.6 Select transfer box control unit and read out fault memory.
2.7 Are there entries in the fault memory?
2.7.1 If YES: > Step 2.8
2.7.2 If NO: > Step 2.9
2.8 Is fault code 2039 entered in the fault memory?
2.8.1 If YES: Print out fault memory log (report No. 3/2.8), continue > Step 3.
2.8.2 If NO: Carry out remedial measures according to > POSES, Diagnosis, 39 - Transfer box. End of troubleshooting/measure.
2.9 End diagnosis and disconnect PIWIS Tester from the diagnostic socket. Take the vehicle on a short test drive (approx. 1.5 miles/2.5 km). During the test drive, activate the "Low Range" driving program in both program stages (automatic/fully engaged center differential lock).
2.10 After the test drive:
Connect PIWIS Tester and switch on ignition and PIWIS Tester. Start diagnosis.
2.11 Select transfer box control unit and read out fault memory.
2.12 Print out fault memory log (report No. 4/2.10).
2.13 Erase fault memory, end diagnosis and switch off ignition.
2.14 Switch the ignition on and start diagnosis again.
2.15 Select transfer box control unit and read out fault memory.
2.16 Are there entries in the fault memory?
2.16.1 If YES: > Step 2.17
2.16.2 If NO: > Step 4
2.17 Is fault code 2039 entered in the fault memory?
2.17.1 If YES: Print out fault memory (report No. 5/2.17), continue > Step 3.
2.17.2 If NO: Carry out remedial measures according to > POSES, Diagnosis, 39 - Transfer box. End of troubleshooting/measure.
3. Static fault (= warning message persists after the engine is restarted).
3.i Switch off ignition.
3.2 Check the plug connection of the servo motor. To do this, raise the vehicle and disconnect the 10-pin plug connection (center differential lock) of the servo motor installed in the transfer box, see POSES, Workshop Manual, Group 3, 39 78 19 - Removing and installing servo motor on transfer box.
3.2.1 Visually inspect the contacts in the plug for signs of damage (e.g. corrosion, deformation). Replace damage contacts, see Cartool repair kit for wiring harnesses (compartment 2/1, repair kit 515).
3.2.2 Push plug onto servo motor.
3.3 Check plug connection of the transfer box control unit. To do this, disconnect the control unit plug connection, see POSES, Workshop Manual, Group 3, 39 13 19 - Removing and installing transfer box control unit.
3.3.1 Visually inspect the contacts in the plug for signs of damage (e.g. corrosion, deformation). Replace damaged contacts, see Cartool repair kit for wiring harnesses (repair kit 524).
3.3.2 Wait for at least approx. 30 before reconnecting the plug to the control unit.
3.4 Switch the ignition on and start diagnosis.
3.5 Select transfer box control unit and erase fault memory.
3.6 End diagnosis and switch off ignition.
3.7 Switch the ignition on and start diagnosis again.
3.8 Select transfer box control unit and read out fault memory.
3.9 Are there entries in the fault memory?
3.9.1 If YES: > Step 3.10
3.9.2 If NO: End of troubleshooting/measure.
3.10 Is, among others, fault code 2039 entered?
3.10.1 If YES: Replace servo motor on the transfer case, see POSES, Workshop Manual, Group 3, 39 78 19 - Removing and installing servo motor on transfer box. End of troubleshooting/measure.
3.10.2 If NO: Carry out remedial measures according to see POSES, Diagnosis, 39 - Transfer box. End of troubleshooting/measure.
4. Sporadic fault (= warning message no longer present after the engine is restarted).
4.1 In order to determine the fault, it is necessary to drive the vehicle - irrespective of time sequence and/or interruptions - until the "4-wheel drive system faulty" warning message is again displayed in the instrument cluster.
Please inform the customer about this situation and ask for the customer's support - especially with regard to the customer's personal driving style, which might be more likely to cause a fault entry to be stored or the warning message to appear than would be the case if somebody else were to drive the vehicle.
After display of the (sporadic) warning message:
If the vehicle can continue to be driven (also with interruptions in the trip). It should then be brought to the Porsche dealership as soon as possible.
Note:
If the warning additionally appears after the engine is restarted during the aforementioned journey (= static fault), this has a different cause and does not have any connection with the determination of the fault. In this case, the vehicle should be promptly brought in to the Porsche dealership to have the fault remedied.
4.2 Connect PIWIS Tester and switch on ignition and PIWIS Tester. Start diagnosis.
4.3 Select transfer box control unit and read out fault memory.
4.4 Print out fault memory log (report No. 5a/4.4).
4.5 Erase fault memory, end diagnosis and switch off ignition.
4.6 Switch the ignition on and start diagnosis again.
4.7 Select transfer box control unit and read out the fault memory.
4.8 Are there entries in the fault memory?
4.8.1 If YES: > Step 4.9
4.8.2 If NO: > Step 4.10
4.9 Is fault code 2039 entered in the fault memory?
4.9.1 If YES: > Step 3
4.9.2 If NO: Carry out remedial measures according to > POSES, Diagnosis, 39 - Transfer box.
End of troubleshooting/measure.
4.io End diagnosis and switch off ignition. Replace servo motor on the transfer case, see POSES, Workshop Manual, Group 3, 39 78 19 - Removing and installing servo motor on transfer box.
4.11 After installation of the servo motor: Switch the ignition on and start diagnosis.
4.12 Select transfer box control unit and erase fault memory.
4.13 End diagnosis and switch off ignition.
4.14 Send the servo motor with the warranty-processing bar code and the prepared reports (= fault memory logs, customer statement) to the Atlanta Warranty Test Center.
End of troubleshooting/measure.
Parts Information:
References:
POSES, Diagnosis, Cayenne:
> 39 - Transfer box
POSES, Cayenne Workshop Manual:
> Group 3: 39 13 19 - Removing/Installing transfer box control unit 39 78 19 - Removing and installing servo motor on transfer box
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