When measuring the resistance of a multi-speed blower motor, if the readings are high to common 10, med to common 12, low to common 14, and start to common infinity, what does this indicate?

The readings from the multi-speed blower motor indicate that the motor is experiencing an open start winding. When measuring resistance, 'high to common', 'med to common', and 'low to common' readings show increasing resistance values, which is expected as different windings are engaged at different speeds. However, the 'start to common' measurement being infinity signifies that the start winding is not closed; thus, there is an open circuit present in that winding.

This open condition prevents the motor from starting properly because the start winding is crucial for initiating motor operation. The design of the motor typically employs a start winding that works in conjunction with the run winding during startup, and if that start winding is open, the motor cannot achieve the necessary torque to start or may not start at all.

In this case, the other options do not align with the resistance readings. If the motor was functioning properly, a finite resistance would be expected across all windings. A shorted winding would typically show a very low resistance reading, not high or infinity. Lastly, a grounded winding would also show abnormal resistance readings, typically indicating a measurement of zero or near zero resistance between the winding and the frame, which is not the case here. Hence, the data clearly point to