Why would the condensing unit fan shut off but not the compressor?
It fires up fine and then cycles through the fan working and not working [while the compressor is still on].


If it's NOT the capacitor, then the fan motor is kicking out on over heat via its integral thermal overload. You need a new fan motor (save the blades from the old one).



I don't bother with testing capacitors. Both fan and cap get swapped out on a 14yo unit. If it can start and run for a while, I highly doubt it's the cap, but you should replace that $5 item regardless. The bearings on the motor may be fine but that doesn't mean the windings are ok (failed windings will lead to thermal overload even though it 'works').

Most integral overload sensors reset themselves. That's why it comes and goes every five minutes.