My cruise control light is flashing green
Unable to set it also the check engine light is on
Occasionally it will stop and the engine light is off also so the cruise light
Still unable to get it to work
I had this issue on my car yesterday good advice for you is to take it to your local auto parts place and get the code reader on it you have a check in my light for a reason and in that regard is why your cruise control light is blinking.I have a 2009 Subaru WRX I had a PO 44 which was a gas cap issue find out what codes he may have definitely research on in the Subaru forums you’ll be able to find your answer
Cruise control is designed to not engage while a CEL is on. Do have codes read, but if you don't know car diagnostics, that isn't going to tell you much. Check/tighten the gas cap as that's probably the leading cause of a CEL. If that doesn't work, have it diagnosed by someone who knows what he's doing. This isn't a big problem and should be easy to correct.