Passenger window rolls up and down on its own

2009 BMW 328
146,000 MILES • 6 CYL • 2WD • AUTOMATIC
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DIVIDES
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Convertible. When driving with everything closed no issues. Once the top is down and windows are down and am driving the passenger window just goes up and down on its own.
Jan 14, 2022 at 5:27 PM
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DIVIDES
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Oh, and the switch on that window doesn't work. Can only roll window up and down from main switch.
Jan 14, 2022 at 5:29 PM
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Correction, the switch on that side works erratically. If it's down while it is down too and i roll it up it goes up and stops every few inches. Won't roll down with the switch. But all good from main switch.
Jan 14, 2022 at 5:32 PM
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JACOBANDNICKOLAS
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Hi,

This is an interesting one if the window goes fully up and down on its own only when the top is open. Since it is moving, we know it isn't a power issue. That leaves the convertible top module, which should open the windows about 1/2 way to prevent damage when the top is opening.

Here is what I suggest: Since we are dealing with the convertible top control module, we really should scan the can-bus to see if there are codes stored.

CAN stands for controller area network. Basically, all modules/computers are tied together via a few wires. By scanning the CAN, it will retrieve codes regardless of the module storing them.

Here is a link showing how it's done:

https://www.2carpros.com/articles/can-scan-controller-area-network-easy

If possible, try this and let me know if codes are retrieved and what they are.

Take care,

Joe
Jan 14, 2022 at 10:25 PM