Measure the voltage on the AD power supply . Verify the 120 VAC input and 12 VDC output.
Measure the voltage at P2 on the 8M PCB . Use a multimeter with needle-tip probes. The voltage must be 12 VDC.
Note: Do not measure the voltage with the cable disconnected.
If the voltage is not correct, measure the voltage at P35 for CHC or P18 for NGC on the PDIST PCB. The voltage must be 12 VDC. If the voltage is correct, cable 860 is at fault. If the voltage is not correct, troubleshoot the PDIST PCB.
If the voltages are correct and 12 VDC is going to the motor but it does not rotate, the motor may have failed. The motor should read 6-12 Ohms of resistance.