F) Freeze Timer (S4 Dip Switch 9 & 10); G) Float Switch Control (S5 Dip Switch 1 Through 5); Control Board Check Procedure - Hoshizaki KMD-850MAH Service Manual

e) S4 Dip Switch 7 & 8
Factory set for optimum performance. Do not adjust.
f) Freeze Timer (S4 dip switch 9 & 10)
Adjust to proper specification, or the unit may not operate correctly.
The freeze timer setting determines the maximum allowed freeze time to prevent
possible freeze-up issues. Upon termination of freeze timer, the control board initiates
the harvest cycle. After 2 consecutive timer terminations, the control board shuts the
machine down. In this case, see "IV.B.3. Low Ice Production" for possible solutions.
The freeze timer is factory adjusted and no adjustment is required.

g) Float Switch Control (S5 dip switch 1 through 5)

Do not adjust. These must be left in the factory default position or the unit will not
operate properly.

4. Control Board Check Procedure

Before replacing a control board that does not show a visible defect and that you suspect
is bad, always conduct the following check procedure. This procedure will help you verify
your diagnosis.
1) Check the S4 dip switch settings to assure that #3, 4, 7, 8, 9, & 10 are in the factory
default position. Switches 1, 2, 5, & 6 are cleaning adjustments and the settings are
flexible. Check the S5 dip switch settings to assure that they are in the factory default
positions. For factory defaults, see "II.C.3.a) Default Dip Switch Settings."
2) Move the control switch to the "ICE" position. The red "POWER OK" LED should come
on. If the red LED is on, the control voltage is good and you can proceed to step 3. If
the red LED is off, check the control transformer secondary circuit. The transformer
secondary circuit includes the cleaning valve interlock switch. Make sure the interlock
switch is closed; otherwise, no control voltage is supplied to the K2 connector.
Transformer output is 10.5V at 115V primary input. If the secondary circuit has proper
voltage and the red LED is off, the control board is bad and should be replaced.
If the secondary circuit does not have proper voltage, check the control transformer
primary circuit. Check for 115V at the 10-pin connector. Check the brown wire at
pin #10 to a white neutral wire for 115V. (Always choose a white neutral wire to
establish a good neutral connection when checking voltages.) For additional checks,
see "IV.B.1.[1] The icemaker will not start."
CAUTION
Dip Switch Setting
(minutes)
No. 9 No. 10
OFF OFF
OFF ON
ON OFF
ON ON
23
Time
60
50
70
60