Fault code 1520: Diagnosis/troubleshooting

WARNING: This page is about a different car, the 2006 Porsche Cayenne, 2005 Porsche Cayenne, 2004 Porsche Cayenne, and 2003 Porsche Cayenne. However, it is still accessible from the selected car via links, so may be relevant.

DIAGNOSIS TROUBLESHOOTING PROCEDURE

Work instruction			Display OK	If not OK
1	Check coding in wiper motor control module and vehicle electrical system control module, and change if necessary	Select the required coding under menu item Coding using the Porsche System Tester II No. 9588	Go to Step 2	Code vehicle electrical system and wiper system control module correctly. With or without driving light assistant and rain/light sensor → End
2	Check the power supply of the rain sensor/light sensor	Check voltage between pins 1 and 2 of rain/light sensor plug	Voltage is 11.4 to 14.5 V Go to Step 3	Repair wire or replace wiring harness → End
3	Check windscreen and silicone cushion for faults and soiling	Carry out a visual inspection to see if there are any cracks, chips or soiling on the windscreen or on the silicone cushion in the area of the rain/light sensor	Go to Step 4	Repair damage or clean any soiling → End
4	Check signal lead for short circuit to B+	Switch off ignition Pull off/disconnect wiper motor plug Pull off/disconnect rain sensor plug Switch on ignition Measure voltage between pin 5 of wiper motor plug and ground	< 0.3V Go to Step 5	Repair wire or replace wiring harness → End
5	Check signal lead for short circuit to ground	Measure resistance between pin 5 of wiper motor plug and ground	∞ Ω Go to Step 6	Repair wire or replace wiring harness → End
6	Check signal lead for open circuit	Measure resistance between pin 5 of wiper motor plug and pin 3 of rain/light sensor	< 5 Ω Go to Step 7	Repair wire or replace wiring harness → End
7	Replace rain sensor/light sensor		→ End