Volvo: check engine light reset, mass flow sensor, air mass

Question
I had a brief problem with the my '93 240 wagon stalling.  Experience tells me
it's the air mass flow sensor.  I checked out the connections, tightened things
up and it seems to run fine.  I want to reset the "check engine light" to see if
it comes back on, before I take it in to a professional.  How do I reset using
that button and blinking light in the little box at the left rear area of the
engine compartment?

Answer
Steve,
Plug into A2 press once the codes will flash 121 for MAF. Press again and see that it is the only code present. Once you have read all the codes press and hold buttom for 5 seconds the light will light and press again for 5 seconds. Just in case all that fails disconnect the battery for a few minutes.