Yeah, disconnect the battery and wait 15-20 minutes before disconnecting the side airbag. Make sure to not reconnect the battery until the airbag is reinstalled, especially if you don't have a way to clear airbag errors.

You do need to remove the speaker to access some of the cables, but the speaker is just one cable and 3 screws to remove, so it hardly adds any time to the job.

I've tried several methods to get the glass to go up when the window regulator fails in the down position, but cutting the cables seems to be the most straightforward. Obviously it's destructive, but it's not like you can reliably fix a broken window regulator anyways, so chances are that you'll be replacing the whole regulator assembly regardless. The motor is usually fine, and you can transfer it over to the new regulator assembly with ease.

I highly recommend have somebody help you with this job, as you'll need a way of supporting the glass in the correct position for removing the glass and reinstalling the glass.

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2003 X5 4.6 | 2000 540i Touring

Formerly owned:
2004 Range Rover | 2000 M5 | 2000 540i/6
1995 750il | 2003 Mercedes S500 | 2003 540i/6