Convertible-top compartment lid pot. fault: Diagnosis/troubleshooting

DIAGNOSIS/TROUBLESHOOTING FOR FAULT CODE 4 - STEPS 1 & 2

Work instruction			Display OK	If not OK
1	Preparatory work for step 2: Ignition on Connect Porsche System Tester II 9588 and call up the data logger in the Actual values menu Select and call up actual value Pot. 2 convertible-top compartment lid		Step 2
2	Check voltage characteristic from Pot 1 convertible-top compartment lid while opening and closing	Close convertible top completely until it has reached its final position and open it again observe the voltage characteristic in the process repeat the process if necessary	the voltage characteristic has a continuous path (similar to that illustrated in the figure below) Step 3	the voltage characteristic indicates unusual deflections (peaks or similar deviations) Step 7

NOTE:

• Fig 1 illustrates the voltage characteristics upon opening the convertible top!
• The voltage characteristics upon closing the convertible top result in a mirror image!

Fig 1: Identifying Voltage Characteristics Upon Opening/Closing Convertible Top (As Of Model Year 2003)

Courtesy of PORSCHE OF NORTH AMERICA, INC.

DIAGNOSIS/TROUBLESHOOTING FOR FAULT CODE 4 - STEPS 3 TO 8

Work instruction			Display OK	If not OK
3	Calibrate convertible top using Porsche System Tester II 9588 Erase fault memory Completely open and close convertible top 3 times Read out fault memory again		Fault code 4 not stored ->End	Fault code 4 stored Step 4
4	Check wires between potentiometer (convertible-top compartment lid) and convertible top control unit for short circuit to positive	Ignition off Pull off plug C on convertible top control unit Pull off plug from potentiometer (convertible-top compartment lid position) Ignition on Measure voltage between plug C pin 1 and ground Measure voltage between plug C pin 3 and ground Measure voltage between plug C pin 5 and ground	< 0.3V Step 5	Repair wiring harness ->End
5	Check wires between potentiometer (convertible-top compartment lid) and convertible top control unit for short circuit to ground	Ignition off Measure resistance between plug C pin 1 and ground Measure resistance between plug C pin 3 and ground Measure resistance between plug C pin 5 and ground	Step 6	Repair wiring harness ->End
6	Check wires between potentiometer (convertible-top compartment lid position) and convertible top control unit for short circuit	Ignition off Measure resistance respectively between plug C pin 1 and: Pin 2 Pin 3 Pin 4 Pin 5 Measure resistance respectively between plug C pin 3 and: Pin 2 Pin 4 Pin 5 Measure resistance respectively between plug C pin 5 and: Pin 2 Pin 4	Step 7	Repair wiring harness ->End
7	Replace potentiometer (convertible-top compartment lid position) Calibrate convertible top using Porsche System Tester II 9588 Erase fault memory Completely open and close convertible top 3 times Read out fault memory again		Fault code 4 not stored ->End	Fault code 4 stored Step 8
8	Replace convertible top control unit		->End