Service diagnostic found that the blower motor was constantly running as long as the air handler had power. I isolated the thermostat and the fan continued to run. I also disconnected the G wire and the fan was still running. The motor was not getting any signal voltage to run but was still running. Options for repair were presented to the homeowner. He chose to have the blower motor replaced. I picked up the new motor and returned to the job. I replaced the blower motor and function tested the system. I let the system run until it reached its set temperature and shut down. The blower motor shut down when the system reached the set temperature. The system was running at the completion of service.