Troubleshooting Chart
20
©2007 Viking Preferred Service
Symptom
Possible Cause
Test Procedure
Corrective Action
Auto Light mode
does not operate.
Failed MPCB.
With unit powered and Auto Light
activated, cover the light sensor.
Measure voltage on VT/BK of 6-
pin door connector to WH on 2-pin
door connector. Voltage should
read 1/2 the AC power supply (120
VAC).
Incorrect voltage,
replace MPCB.
Failed Main dispenser
switch (failed short).
Disconnect power. Remove both
leads from the switch and
measure resistance across switch
terminals. Resistance should read
higher than 10 M
Ω
when switch is
open and less than 1
Ω
when
switch is closed.
Replace switch.
Ice or Water
dispenser
mechanism runs
continuously.
Failed MPCB.
With unit powered, measure
voltage on pin 1, 2, or 3 of J1.
Voltage should read 0 VAC.
Voltage present,
replace MPCB.
Filter Status LED
never changes to
red.
Failed PCB.
Verify with the user if unit has
been unplugged for a long period.
Demonstrate reset operation to
customer.
Replace water filter
and reset Filter
Status.
Replace
MPCB if problem
continues. Customer
education.
Failed solenoid.
Disconnect power. Remove both
leads from the solenoid and
measure the resistance across
solenoid terminals. Resistance
should read 101.2 ± 10%.
Replace solenoid.
Auger motor
operates in Cubed or
Crushed mode but
ice door chute never
opens.
Failed MPCB.
With unit powered and auger
motor operating, measure
approximately 55 VAC on pin-4 of
J1 on MPCB.
No 55 VAC, replace
MPCB.
Auger motor
operates in Cubed or
Crushed mode but
ice door chute never
closes.
Failed MPCB.
Measure voltage on pin-4 of J1 on
MPCB. Voltage should read
approximately 55 VDC when ice
chute door is open (solenoid
energized) or 0 VDC when closed
(solenoid not energized).
Incorrect voltage,
replace MPCB.
No LED lit, Water
dispenser operates,
auger motor
operates only in
Cubed mode and ice
chute door does not
open or remains
open.
Failed MPCB.
Replace MPCB
No LED lit, Water
dispenser operates,
auger motor
operates only in
Cubed mode and
dispenser light is on
continuously.
Failed MPCB.
Replace MPCB.