SERVICE DIAGNOSIS: Ice Level Control Circuit
CONDITION
DETERMINE CAUSE
PROBABLE CORRECTION
Ice Machine does not run, it has
power to it, the high pressure control
is closed, the on/off switch is set to
ON.
A. Listen for a ticking sound from
transducer.
If no noise, go to C. If there is a
noise, check for a light on the board
(models built after 4/93). If there is a
light on, check relay contacts N.O.
and COM. The contacts should be
CLOSED. If closed, go to D. If not,
replace the board. If light is off, or
prior model, go to B.
B. Open bin door and twist
transducer 1/4 turn and pull out. DO
NOT UNPLUG with power
connected. Examine the transducer,
the inside must be clean and dry.
If the inside of the transducer (above
screen) was wet, replace it. Set bin
level to FULL and aim at an object
about 1-3 feet away. Machine should
restart, if not go to D.
C. Check power to bin level control
board.
Should be 12 volts from transformer,
if not replace transformer. If there is
power go to D.
D. Disconnect electrical power and
test ice machine circuit by attaching a
jumper wire between bin thermostat
posts on circuit board part no.
12-1912-01 (the circuit board with the
timer on it). Reconnect power.
If machine does not start go back to
machine circuit. If machine starts,
disconnect electrical power, remove
jumper wire and reconnect electrical
power. Then go to E.
E. Transducer or ice level board
assembly defective.
Replace transducer. Set bin level to
FULL and aim at an object about 1-3
feet away. Machine should restart. If
this does not repair unit, replace the
board.
Machine runs, makes ice, switches
on and off, but ice level cannot be
controlled.
Ice level switch may be defective. On
boards with a light, check by moving
switch & watching light.
Replace ice level switch
Machine runs, but will not shut off.
Board relay stuck closed. Check
relay.
If COM and N.O. are closed when
power is off, replace board. If open,
go to B above.
PARTIAL VIEW OF
CIRCUIT BOARD
12-1912-01
BIN THERMOSTAT
PLUG - IN
RELAY
POSTS MENTIONED
IN “D” ABOVE
TIMER
Electrical Shock Hazard
Can Cause Personal Injury.
Disconnect Power Before
Servicing.
Bin Thermostat Posts at
Line Voltage.
CMS1202
September 1993
Page 22
