How did you test them, they normally go low in capacitance, or start to break down internally. The 1.75uF one is likely the power supply capacitor, the dual unit will be the one used to give the phase shift for the shaded pole motor, and is switched to give the speeds. If the single capacitor is low capacitance the motor will start up but the controller will lose power.
Also check the electrolytic capacitors on the board, there will be a power supply that is 100-470uF around 16V or so, and if it is low the same symptom.
Photo of the board will help as well