I have just bought a 1998 S70 and the recirculation button as well as the off button flash for about 15 seconds when I turn on my A/C on the AUT setting. I have already had it looked at once and they fixed the blower and added more freon (sp?). What else could it be? I live in NC and it has been really hot (temps above 93) and high humdity, is this to blame?

There is a mode where the recirc button flashes to tell you it
will only be used for a few minutes (then it gos back to vent from
the outside). I see this if I press recirculate and hold it down
for a couple of seconds. If I press quickly I don't see the flash.
Manual has details (not the best user interface, thats for sure).

But, flashing lights also are used to indicate a system problem.
Are you getting cold air. In other words is it working except
for the flashing light? If it is not working, a dealer needs
to pull the error codes from the system as the first start in
determining what is wrong.

I do get cool air from the A/C. The recirculation button and the off button only flash for a few seconds when the car is first turned on. What else could be wrong?

It is really hard to say what is wrong since there are probably
many things. The system stores a code that indicates why it
flashed the lights and the dealer has to read the code.

I just checked the manual and if both lights flash that indicates
a problem. The dealer will have to pull the error codes stored by
the system.