Porsche Repair Questions? Ask a Mechanic for Answers ASAP
Did you check the socket that the bulb fits into? These often not burn spots on them. I always replace the socket and bulb
That socket superseded to a new part number also 955 631 133 01 dealer list $7.57. I would also try pushing in on the headlight while having the turn signal on. If it starts blinking, there is a connection issue with the slide in headlamp connection. You should also look inside the headlight contacts where the bulb socket sits. Check for burned contacts. You can take a small pocket screwdriver or similar tool and try bending the contacts in the headlight so it will have a more positive contact with the socket.
Do not feel like you are alone. Headlight and front turn signal problems plagued first generation Cayennes. But it can be fixed. Next time you pull the headlight, take the main cover off to gain access to the main and high beam bulbs. Look inside there and see what the condition of the wires is. The insulation is starting to fail on these cars. Not just Porsche but other makes also.
I just wrote a ton of info and a refresh killed it! OK, adjust the gap to the speed sensor like I said previously. Make sure the reference sensor is not above the allen. Turn the engine to get the allen away from the sensors. Loosen the allen bolts, push down til the speed sensor hits the flywheel. Pick up ever so slightly just to put a tiny gap between the speed sensor and the flywhel. This will make the reference sensor correct. Rotate the engine by hand several times before cranking the engine to make sure nothing hits or scrapes. Either remeasure voltage or try to start the car. If the injectors start clicking your in good shape.
Actually that was for another problem, disregard sorry.
I am here when you can come back and discuss what to do. Thanks