NF, what AB said is that in the pre-LCI E90, the DRLs are both the AEs and XNs. And as E46F said, in the LCI E90, the DRLs are only the AEs. The ILs and TLs are not on when you choose the DRL option. (Sorry, sorry, just joining in the fun
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And you don't need your dealer SA to set things up for you, it's all very easy to set up or change with the OBC or iDrive, depending on the model. The SA probably can't change the program for the pre-LCI DRLs, but no harm asking.