Glad to help. I researched other 2014/15 BMWs and tried their tail light DRL values. Worst case was just having to code back to defaults. Thanks for updating the Facebook i3 coding file - I've learned a lot from that group!
You should see a toggle for DRLs under:
Menu > Settings > Lighting >...
These values work on my i3 (shipped with i-level I001-15-03-502). The DRL setting in iDrive controls the tail lights as well.
BDC_BODY
3064 → MAPPING_TAGFAHRL_1_H_L_OUTPUT → sl_l
3064 → MAPPING_TAGFAHRL_1_H_R_OUTPUT → sl_r
3065 → MAPPING_TAGFAHRL_2_H_L_OUTPUT → sl_2_l
3065 →...
