AT Steptronic Shift Went Out, Much More Followed!

[trackie]

I need help with a 2009 128i. First off, its overdue for oil change and brake rotors are worn, but hopefully those are unrelated.

A month after an airbag recall, the steptronic shifting went out on the gear shifter but not the paddles. I suspected the wiring under the shifter, but hadn't inspected them yet. After this, malfunctions happened in quick succession. First ABS and DSC goes out. Now while turning and braking above 10 mph, the brake pedal hardens and gives a 'bungee' sound. Next, a passenger airbag warning and then an intermittent low battery warning.

Then the car shut down while driving. Not able to figure it out, I towed it to the dealer, only to have them put gas in it and it start right up. Apparently the fuel gauge gave a faulty reading of about a fourth of a tank when it was actually empty.

Tow was $200, Dealer is already at $150, and now wants $350 to switch the wheel speed sensors and run extra diagnostics. I asked them to look at the shifter wires instead, just lifting the base plate at least, and they declined, only willing to take the whole assembly out and quote $350 for that as well, not willing to do the more simple panel removal as I requested instead. I'm guessing they don't teach soldering to their mechanics, either, so this would naturally lead to a quote for replacing the entire a$$embly. I really wish I knew of a good local mechanic, but I'm unaware of any in my area.

So, is it possible all these issues could be caused by a gear shift wire, such as a ground? Since this was the first malfunction, it makes sense to me. I was literally JUST about to change the oil, rotors, and inspect the wires at home when this happened.

In the future, I'll be sure to put extra fuel in a car before getting a tow... I really appreciate any help on this.

[gjm120]

There is a common issue with the wiring on the Steptronic that stops it from going into sport mode. If I recall correctly, the wiring is routed such that it's prone to wear and break. Maybe the same issue caused your AT problem. Just search for something like "bmw steptronic sport mode won't engage".

I don't have anything to offer on the other stuff that hit you.

Good luck.