[houtan]

I got through a lot of troubleshooting so I am going to start updating the thread in logical chunks.

Using the PT CANBUS wiring diagram from ista, I located each module to verify ~60 ohms at each connector. All connections had 60ohms. The only connector I did not test at the actual connector was for the transmission. It was going to take a lot of work to get to and the wiring seemed intact. What I did instead is verified 60ohms and connector x6021, which has two sets of canbus wires going from it to the transmission. Then I checked for continuity between the CAN HI and LOW wires going to the transmission and both checked out. So I called it good for now.

Now that it seemed like my wiring was good, i decided the next step was to or a Pico 2204a oscilloscope. While I waited for that to get delivered, i decided to try and flash my DSC again. It felt like the BMW gods were with me that night, because the flash worked! I was really confused because I didnt do anything to fix the error. Just to see what happens, i decided to put all my connections back to each module and start up the car crossing my fingers somehow the car is fixed. But nope, code came back after 5 or so minutes.

Next post i will share my testing with the pico 2204a.

I am also attaching a picture of x6021 and the CANBUS wires that go to the transmission.