8007 CDR23: Diagnosis/troubleshooting

DIAGNOSIS/TROUBLESHOOTING - 8007 CDR23

Work instruction			Display OK	If not OK
1	Read out CDR23 fault memory	Connect the Porsche System Tester II 9588 to the diagnostic socket; switch on the ignition and the Porsche System Tester II 9588 Select 986 as the vehicle type and start the automatic control module search In the Control units menu, select CDR23 Click the ">>" key in the Fault memory menu Read out fault memory Erase fault memory Remove ignition key and switch on ignition again Read out fault memory Extract ambient data, press the ">>" key	The fault is remedied -> End	Fault code is still displayed Step 2
2	Check MOST components	In the Control units menu, select CDR23 Click MOST components check in the function selection menu and start it with the ">>" key Wait for the end of the automatic check The duration of the check depends on the number of existing MOST control modules Press the ">>" key	CDR23 > amplifier optically OK electrically OK Amplifier > CD changer optically OK electrically OK CD changer > CDR23optically OK electrically OK	An optical fault is displayed 3 An electrical fault is displayed 4
3	Optical fault	Replace the relevant optical waveguide between the listed faulty components with the optical waveguide test line 9712 that is provided as a special tool. Check MOST components again	Replace the faulty optical waveguide with the relevant spare part -> End	Replace the relevant recipient MOST control module Step 2
4	Check diagnosis distribution line for open circuit	Check diagnosis distribution line between the listed faulty components for an open circuit Switch ignition off Disconnect the plug connections of the existing MOST control modules Measure the resistance of the diagnosis distribution line between the relevant plug connections	< 0.5 Step 5	Remove open circuit in diagnosis distribution line -> End
5	Check diagnosis distribution line for short circuit to ground	Check diagnosis distribution line between the listed faulty components for short circuit to ground Switch ignition off Disconnect the plug connections of the existing MOST control modules Measure the resistance of the diagnosis distribution line to ground	Step 6	Remove short circuit to ground in diagnosis distribution line -> End
6	Check diagnosis distribution line for short circuit to B+	Check diagnosis distribution line between the listed faulty components for short circuit to B+ Switch ignition off Disconnect the plug connections of the existing MOST control modules Measure the voltage of the diagnosis distribution line to ground Switch ignition on	0 V Step 7	Remove short circuit to B+ in diagnosis distribution line -> End
7	Replace PCM2		-> End