Code 420571, Transmission malfunction?

2013 BMW X3
175,000 MILES • 2.0L • 4 CYL • 4WD • AUTOMATIC
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ASHOK SAINI
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The following code shows up 420571 ETC voltage supply: Outside of specified range (below 6.5V).

When I am stopped on a red light and vehicle is in drive, it switches to parking sometimes and if otherwise it stays in drive, but this above code appears and vehicle won't move ahead unless the lever goes back in parking, and I manually put the vehicle in drive myself.

As it shows above voltage below 6.5 could it need a battery change, it not been changed from 8 years, but I don't have any issues with starting.
Sep 19, 2023 at 12:01 PM
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STRAILER
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Yes, this code means you need a new battery. Here is how to change it out and please clean the battery cables as well.

This guide can help:

https://www.2carpros.com/articles/everything-goes-dead-when-engine-is-cranked

Check out the images (below). Please let us know if you need anything else to get the problem fixed.
Sep 21, 2023 at 9:41 AM