My airconditioner stops blowing cold air after a trip to town and being shut off and on again. Sometimes I can get it started cooling by pressing the off switch several times. My husband said it gives him a readout code ( "mil" is off.) What does that mean?

Check to see if there is too much or not enough refrigerant charge in the system. Check to see if the air conditioner clutch is engaging by observing the compressor pulley area to see if the center is spinning (meaning it's engaged) while the engine is running and the a/c is on after you turn it off and on again.

I do not know what the 'mil' code means.