PCM2 System - Diagnosis and Repair
911(996)8/03 9110
Binder - 9, Electrics
Date: 10-20-04
This bulletin replaces bulletin Group 9, # 8/03, dated 5-23-03.
Diagnosing And Repairing The PCM2 System
Vehicle Type:
911 Carrera (996)/911 Carrera 4 (996)
Model Year:
From '03 (3)
Concerns:
Diagnosing and repairing the PCM2 system, Porsche Communication Management (PCM2) (Option - M665) see Table below.
Information:
The information in this bulletin is organized by "Complaint" and "Work Procedure". The work procedure steps describe in the following listing are identical for both Porsche testers, PST2 and PIWIS.
Complaint:
Telephone - Repeated PIN query while traveling.
Frequent (short-term) sound failure.
Sound failure and error messages after system start:
Amplifier not available"; "CD changer not available"; "Telephone not available".
Only at component temperature (not outside temp.) between 14° F (-10°C) to 32° F (0°C).
Components:
All MOST components
(Only applicable to components whose part number index is lower than the part numbers listed in the note under Step 2)
Remedy:
Software update PCM2 ~ MOST system test ~ Compare unlock and transmission error counter.
Work Procedure:
1. Software Update
Carry out the software update for the PCM2 in accordance with Technical Information Group 9, # 2/03 - "Software update in the Porsche Communication Management (PCM2)".
1.1 If the defect is still present, continue with Step 2.
2. MOST system test or troubleshooting via the unlock and transmission error counter.
Only for PCM2 system components whose part number index is lower than:
PCM2 with amplifier, 996 642 224 04 PCM2 without amplifier, 996 642 234 04 Harman amplifier, 996 645 331 03 BOSE amplifier, 996 645 333 04 CD changer "CDC", 996 645 140 02 Telephone control module, 996 642 207 04
Since this fault type only occurs at a system component temperature (not outside temperature) of 14° F F10° C) to 32° F (0°C), these can only be localized at these temperatures. If the system components warm up so that the temperature exceeds 32° F (0°C) with the PCM2 switched on during troubleshooting, the faults can no longer be localized.
2.1 MOST System Check
2.1.1 Perform a MOST system test with the PSJ2 or PIWIS Jester. See Technical Manual, Group 0, Diagnosis, Chapter: 9101 - MOST optical/electrical.
2.1.2 Correct fault according to Technical Manual, Group 0, Diagnosis, Chapter: 9101 - Fault overview MMI.
2.1.3 If there is no longer a defect, the repair is accomplished.
2.1.4 If the detect is still present, but no fault can be determined, continue with Step 2.2.
2.2 Troubleshooting based on the unlock and transmission error counter.
2.2.1 Allow the components of the PCM2 system connection to cool until it is ensures that the temperature of the components is in the range of 14° F (-10° C) to 32° F (0°C).
2.2.2 Using the PST2 or PIWIS Tester in the PCM control module, select the MOST component check and select the menu item "Reset all coding/transmission counters'. Quit the menu and disconnect the PST2 or PIWIS Tester from the vehicle.
2.2.3 After operating the PCM2 or after the sound failures have occurred again, read out the unlock and transmission error counter using the PST2 or PIWIS Tester. Using the PST2 or PIWIS Tester in the PCM control module, select the MOST component check and select the menu item "Read all coding/transmission counters.
Note:
In order to have a clear comparison of the unlock and transmission error counter (before/after), it is helpful to save these in the PST2 or PIWIS Tester and print them out
2.2.4 The unlock and transmission error counter provide information about the number of interruptions (MOST unlock counter) and data transmission faults (MOST transmission errors) of the communication between the individual components. If one of the components has a significantly higher number of faults, this components will be regarded as the fault source.
2.2.5 Using the special tool "optical waveguide test line (9712)", jumper the MOST distribution line to the component identified to be faulty in Step 2.2.4. Repeat work steps starting from Step 2.2.1 to Step 2.2.3.
Note:
This procedure allows the MOST distribution line to be tested again without the "faulty" component, other fault sources to be ruled out, and the result of the unlock and transmission error counter to be compared with the result of the installed component. There is no sound output in the PCM system connection, if the external amplifier (I No.490, 680) was jumped.
2.2.6 Replace defective components. See Technical Information, Group 0, # 1/04
Literature:
911 Carrera (996) Technical Manual,
Group 0:
> Entire vehicle - General: 01 - Diagnosis system: reading out fault memory and activating systems.
> Diagnosis: 91 - PCM2 - MMI
> Technical Information: # 1/04 - Return of queried control modules and diagnosable components
Group 9:
> Technical Information: # 2/03 - Workshop Campaign W310 - Software update in Porsche Communication Management (PCM2)
> Technical Information: # 11/03 - PCM2: Spare parts / BOSE amplifier: Spare parts requirement
> Technical Information: # 15/03 - PCM2 with BOSE Sound package: sporadic sound failure
> Technical Information: # 18/03 - Wrong time display in PCM2 and instrument cluster
> Repairs: 9110 19 - Removing and installing display and operator control unit (PCM).
> Repairs: 91 44 19 - Removing and installing the loudspeaker amplifier
Porsche Communication Management (PCM) operating instructions:
> Chapter 1 - Introduction and commissioning