Hoshizaki CUBELET ICEMAKER/DISPENSER DCM-750BAH Service Manual page 19

3. 60 seconds after the "GM" LED comes on, the "COMP" LED comes on, and the
compressor and fan motor start. If the "COMP" LED does not come on 60 seconds
after the gear motor starts, check that the gear motor protect relay contacts (connector
K terminals  and ) have closed. If the "COMP" LED is on and the compressor and
fan motor did not start, check for 5/0V at X (LBU) and X (BR) on the control
board to neutral. If the "COMP" LED is on and there is voltage at X (BR) to neutral
and no voltage at X (LBU) to neutral, the control board is bad and should be replaced.
See wiring diagram "III.C.3. Freeze Cycle" for further details.
c) Dispensing Components DCM-750BAH, DCM-750BWH
. Ice Dispense "Continuous": Pressing the ice dispense switch closes terminals 6 and 5
at the K4 connector. The "DM" LED comes on and the dispensing motor energizes. If
the "DM" LED does not turn on, check continuity through the ice dispense switch and
the dispense mode switch. If the LED is on and the dispensing motor does not start,
check for 5/0V at connector K terminals 3 and 6 to a neutral. With voltage at
terminal 3 and not at terminal 6, the control board is bad and should be replaced.
Note: The agitating motor will operate .6 seconds every  seconds of accumulative
dispense time. See "III.D.. Continuous Dispense."
. Ice Dispense "Portion": Pressing the ice dispense switch closes terminals 6 and 7 at
the K4 connector. The "DM" LED comes on and the dispinsing motor energizes. If the
"DM" LED does not turn on, check continuity through the ice dispense switch and the
dispense mode switch. If the LED is on and the dispensing motor does not start, check
for 5V at connector K terminals 3 and 6 to a neutral. With voltage at terminal 3 and
not at terminal 6, the control board is bad and should be replaced.
Note: The agitating motor will operate .6 seconds every  seconds of accumulative
dispense time. See "III.D.. Portion Dipsense."
d) Dispensing Components DCM-750BAH-OS, DCM-750BWH-OS
See "IV.C.5. Opti Serve (OS) Sensors."
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