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Component Tests and General Diagnostics

Troubleshooting with no control module connected

NOTE: The Porsche System Tester II No. 9588 and the 'vehicle electrical system control module' are not connected.

Overview

Diagnostic conditions
- Ignition on
- The fuses of the 'vehicle electrical system control module' are OK
- The fuses of the 'gateway' in the instrument cluster are OK
- Battery voltage is OK
- Plug on 'vehicle electrical system control module' attached correctly

Possible cause of fault
- Incorrect vehicle type selected in Porsche System Tester II No. 9588
- Porsche System Tester II No. 9588 is not connected correctly or is faulty
- Power supply to the 'vehicle electrical system control module' is not OK
- 'K lead' to 'gateway' in instrument cluster does not function
- 'Gateway' in instrument cluster does not function
- 'CAN comfort (B)' does not function
- 'Vehicle electrical system control module' does not function

Affected pins
Plug 'A' on vehicle electrical system control module:
- Pin 1 'CAN comfort (high)'
- Pin 2 'CAN comfort (low)'
- Pin 21 'input for terminal 15 signal/fuse carrier at left of dashboard (F53)'

Plug 'C' on vehicle electrical system control module:
- Pin 5 'ground input (terminal 31) MB 23'

Plug 'K' on vehicle electrical system control module:
- Pin 1 'input for terminal 30 power supply, interior lights (fuse carrier at left of dashboard, F12)'. The vehicle electrical system control module is also supplied via the interior light power supply. An interior light failure would also indicate a failure of the vehicle electrical system control module.

Plug 'P' on vehicle electrical system control module:
- Pin 13 'input for terminal 30 power supply (fuse carrier at left of dashboard, F36)'
- Pin 15 'input for terminal 31 ground'






Diagnosis/troubleshooting