CayenneHater

The rain sensor wiper operation (intermittent wipe) has stopped working on my Garbage Can 957 S | 78K miles. I have worked through all steps in the Owner's Manual and have not restored functionality. All other wiper-related functions are working. Four rain sensitivity settings can be selected by rotating the barrel in the wiper stalk. Using my Durametric, I can see that each of the four rain sensitivity settings are detected. Likewise, I have verified with a Durametric the wiper stalk positions shown in the Owner's Manual (off, rain sensing, slow, fast, one-touch) are detected. So, the wiper stalk appears to be fully functional. When I move the wiper stalk to position 1, the wipers actuate once. Pouring water over the glass (rain sensor) does not actuate a wipe cycle regardless of wipe interval setting (1-4). EXISTING FAULT CODES - Durametric report attached. Air Conditioning 3: Control Module Faulty Gateway 0414 Control Module Coded Incorrectly Vehicle Electrical System 1117 Load signal generator terminal DF - Implausible signal, test conditions are not-completed, fault is not currently active and is not causing a DTC light Transfer Case 2025 Power supply - Open circuit/short circuit to B+, test conditions are not-completed, fault is not currently active and is not causing a DTC light Tow Bar 576 Terminal 15 Implausible signal The car did not originally have a towing package. I installed a used towing hitch and towing module (scrap yard). The towing module has not been coded to the vehicle. I suspect that explains the Tow Bar 576 fault code. I also think that might explain the Gateway 0414. I might have also swapped out the HVAC controls for a better looking, similar unit which might explain the Air Conditioning fault code. All air conditioning / HVAC features seem to be working. QUESTIONS 1) Does anybody know how I can confirm/investigate rain sensor functionality using the Durametric? I have already verified the plug connection at the rain sensor. 2) Is there any control unit (relay) or other component that I should investigate to resolve the wiper problem? I've looked at wiring diagrams and I don't see a relay or other component, but wanted to confirm. [I am in the process of replacing a "Servotronic Control Unit" to hopefully restore power steering functionality during low speed/parking. This part appears to be a plug-and-play relay, but Porsche had a fancier description for that part.] 3) Any ideas on possible further troubleshooting? Thanks for any input! durametric output.pdf