MacBook Pro 2012 15" can’t boot
The error code indicates that the Apple Hardware Test tested your RAM-modules and found a problem with at least one memory module.  In order to solve this you'll need to have the RAM module replaced (i.e. hardware repair).

If you have the 15" MacBook Pro (mid-2012, non-retina), you can buy a new RAM module yourself and replace it fairly easily.

If you have the 15" Retina MacBook Pro (mid-2012) the RAM module is soldered on the logic board and not easily replaceable. In this case, contact Apple or a repair shop for help.