I just bought a 2001 S60 w/ 80K on it. The A/C clutch cycles on and off about every 15 seconds with the car at idle in park. When I turn the A/C off via the switch, the A/C will not come back on when selected. If I turn the car off and restart it, the A/C comes back on. Any idea what may cause this?

 

It is possible that you are running low on refrigerant.I would get recharge kit for $10 that comes with tester and see if your system's pressure is correct. Should be easy to do. I have done it (with recharge) to three of my cars (not Volvo's though).