Final answer:
A hot compressor with infinite ohm reading between Common and the other terminals and a 4.3 ohm reading between start and run suggests a grounded winding. This situation indicates an electrical fault requiring repair for safe operation.
Step-by-step explanation:
A hot compressor showing an infinite ohm reading between Common and the other two terminals, and a normal reading of 4.3 ohms between the start and run terminals, most likely has a grounded winding. This is indicated by the inability of current to flow between Common and the other terminals, which would not be the case if the issue were simply a disconnected capacitor. Moreover, if the winding was shorted, there would generally be a very low or near zero ohm reading between the terminals, not an infinite one. The condition mentioned in the scenario where the insulation is worn, allowing the live/hot wire to contact the metal case, reinforces the conclusion of a grounded winding and emphasizes the importance of proper grounding to ensure safety, as well as to trigger a circuit breaker for necessary repairs.