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If the AC compressor clutch engages when a jumper wire connects the battery to the power connector, this indicates that the clutch coil itself is functioning properly. The engagement under this condition means that the electrical circuit to the clutch is intact and that the issue likely lies upstream in the compressor control circuit.

In normal operation, the compressor clutch is controlled by the vehicle's climate control system, which includes inputs from various sensors and control modules. If these components are faulty, it may prevent the clutch from receiving the signal to engage during regular operation, leading to a situation where the compressor does not run unless directly powered via a jumper wire.

Understanding this helps clarify why the other options do not fit the situation. For instance, a defective clutch coil would not allow the clutch to engage at all, and low refrigerant levels or a blocked refrigerant line primarily affect system pressure and cooling efficiency, but would not prevent the clutch from being engaged when externally powered. Therefore, the malfunctioning control circuit is indeed the most plausible explanation for the compressor not running normally.