How do you check a start capacitor for ac with no markings on where wires go on capacitor?

To check a start capacitor without markings, first ensure the power is off and discharge the capacitor by shorting its terminals with a resistor. Then, use a multimeter set to the capacitance setting to measure the capacitor's value. If the capacitance reading is significantly lower than the rated value or shows an open or short circuit, the capacitor is likely faulty. If unsure about the wiring, consult the device’s wiring diagram or manual for guidance on proper connections.