As others reported, it didn't work at first - some reviewers mention multiple devices not working in a row. Looking at their illustration in the accompanying manual (if you can call it that), I noticed that the ribbon cable at the M2 end was blue side up, but on my unit it was blue side down - the ribbon cable was inserted the wrong way round . Unlatch the end of M2, flip the ribbon cable over so the blue side is visible from above, then latch it again and everything works great now. Notice that the small black latch on the ribbon cable flips up instead of forward.
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