That's a service schedule reminder. You're due for the A15 service. It varies a little depending on your trim and transmission type. See here for what each service level specifies-
Acura Maintenance Codes for MDX, RDX, RLX, TLX, ILX, TL, TSX, ZDX models near Milwaukee, WI
Maintenance Minder Codes
Acura Maintenance Schedules | Acura Owners Site
Get specific recommendations for service and care for your Acura with the Maintenance Minder System on the official Acura Owners site.