I had the same issue with my car (US Vs Euro spec?). The car came with the backup switch connected to fuse# 3 (as shown in the wire diagram), but if you read the descriptions for each fuse it could go to fuse#12 (switched hot when ignition is on). Just unplug the green wire from #3 and plug it into the unused terminal on #12 and the car is ready for the US market.
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