Here is a short youtube video with the sound my 2004 Porsche Cayenne S is getting when I try to start it. The vehicle has about 130000 miles. I use it as an automatic, but it has this feature I've never used called Tiptronic where you can manually change the gears. No OBDII codes available.
What would you diagnose as the issue? or what should I try next as I diagnose? I watched Scotty's helpful video on diagnosing a car that cranks, but doesn't starts and I didn't feel like I can really say my car is "cranking" when I compare it to your video.
What I know: Without jumping the car I get ZERO signs of electricity on the dash, lights, nothing. If I jump the car with the terminal under the hood, I get the same ZERO signs of electricity. But when I jump the car directly to the battery under the driver's seat, I get dash/radio/locks/seat controls.
When jumping to battery under the driver's seat: If I turn the key in the normal clockwise way, no noise from the engine occurs. But when I turn it to the left and then the right, I get this noise, and the front headlights turn on and off quickly. It is my understanding that turning the key to the left first activates the back up battery. There is no back up battery installed in this car at this time. Only the one under the seat. Anyone got any ideas what this sound is telling me?
I believe the vehicle has a bad alternator. It basically eats batteries. Has to be jumped frequently if not started for even just a couple days. Normally, I'm able to jump it and get it where I need to go. It died at my work and I've been trying to get it started so I can get it home to work on replacing the alternator.
Put a new battery and replace your alternator.
Alternator is supposed keep the battery charged up while driving (so it's fully charged to start the vehicle for next startup) and it also takes over for running the electronics of the car. while your driving. If the alternator isn't doing it's job then you're running the car entirely off the battery, which in modern vehicles can run down pretty quickly. And you can only run down a battery several times before it won't hold a charge anymore. So typically it's the alternator, but you've got a Porsche and that's an expensive part, even for a reman'd one. Good Luck
