I was swapping a sensor in my wife's cayenne and I stupidly shorted the dipstick out to the alternator. now the gateway is having trouble connecting to a few power related sensors. particular the battery sensor, the power distributor and the DC to DC converter (which I think is for stop start).

Do these things connect directly to the gateway or is there a module in between or anything else that can be broken? all fuses in the car were fine, but I'm going to dig around a little more to see if there are any fuses under the hood that might have blown. any other ideas, or anyone have a wiring diagram for this. I would greatly appreciate








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I made some headway today. I think it is the alternator screaming on the bus. My core issue was that I was getting a huge 7amp parasitic drain after shutting off Cayenne and the start stop module was throwing an error when car was running. With the car off I could measure about 7amps of draw with most of it across the DC/DC start stop related circuits. As it got close to dark I decided to pull the Blue Bus Wire from the alternator. After doing so the other modules seemed to be able to talk to each other as Durametric. It go too dark to re-measure the draw but at a minimum, I think I need some new alternator electronics or if I cant buy separately I whole new alternator.

 

It sounds like you need to solve that massive parasitic drain 1st and then start working on what device(s) are affecting bus signaling.

I know BMW buses very well and I know we have can bus on our Cayennes. I haven’t had a minute to identify all of the buses on the 958.

Forum; Do we have a list of the buses in existence in our vehicles and attached devices?

 

I agree the only thing I'm not sure of is could these be problems be married to each other. One of the really heavy drives was on this DC converter circuit. The DC converter module is one of these modules that is on this bus. The Gateway seem to be able to talk to it once I pulled the alternator bus wire. I tried quickly this morning plugging in the battery and seeing what kind of draw I had with the car not running. It was still high but I may not have waited long enough for the car to decide to go to sleep. when I get home today that's my next plan, to retest the parasitic draw circuits