Viking VMOC205BK Service Manual page 22

Rev 1 (May 2011)
PROCEDURE
LETTER
Q KEY UNIT TEST
If the display fails to clear when the STOP/CLEAR pad is depressed, first verify the flat ribbon cable
is making good contact, verify that the door sensing switch (stop switch) operates properly; that is the
contacts are closed when the door is closed and open when the door is open. If the door sensing switch
(stop switch) is good, disconnect the flat ribbon cable that connects the key unit to the control unit and
make sure the door sensing switch is closed (either close the door or short the door sensing switch
connecter). Use the key unit matrix indicated on the control panel schematic and place a jumper wire
between the pins that correspond to the STOP/CLEAR pad making momentary contact.
If the control unit responds by clearing with a beep the key unit is faulty and must be replaced. If the
control unit does not respond, it is a faulty and must be replaced. If a specific pad does not respond,
the above method may be used (after clearing the control unit) to determine if the control unit or key
pad is at fault.
R RELAY TEST
Remove the outer case and check voltage between Pin Nos. 7 and 9 of the 9- pin connector (A) on
the control unit an A.C. voltmeter. The meter should indicate 120 volts, if not check the oven circuitry.
Shut-off, Cook and Heater Relay Test
These relays are operated by D.C. voltage
Check voltage at the relay coil with a D.C. voltmeter during the microwave cooking operation or convec-
tion cooking operation.
DC. voltage indicated ............. Defective relay.
DC. voltage not indicated ........ Check diode which is connected to the relay coil. If diode is good, control
RELAY SYMBOL
RY1
RY2(COOK)
RY3(HEATER)
RY4
RY5
RY6
S COMPU DEFROST TEST
(1) Place one cup of water in the center of the turntable tray in the oven cavity.
(2) Close the door, touch the "DEFROST" pad twice and touch the Number pad "5". And then touch the
"START" pad.
(3) After 2 sec. Now the oven is in DEFROST cooking condition.
(4) The oven will operate as follows.
WEIGHT
0.5lbs
(5) If improper operation is indicated, the control unit is probably defective and should be checked.
TEST PROCEDURES
G 5 G 6
ADD-A-
DEFROST
G 4
MINUTE
G 3
POPCORN PREHEAT
SLOW
G 2 REHEAT
COOK
HELP
G 1
KEY UNIT
unit is defective.
OPERATIONAL VOLTAGE
Approx. 19.0V D.C.
Approx. 18.0V D.C.
Approx. 18.0V D.C.
Approx. 19.0V D.C.
Approx. 19.0V D.C.
Approx. 19.0V D.C.
1ST STAGE 2ND STAGE
LEVEL TIME LEVEL
70% 47sec. 0%
22
COMPONENT TEST
G 7 G 8 G 9 G10
SENSOR CONVEC CONVEC CONVEC
COOK BROIL ROAST BAKE
1 2 3
CONVEC
100°F 150°F 275°F
6 7 8
LOW MIX
BAKE
350°F 375°F 400°F
TIMER POWER
CLOCK
TOUCH ON
LEVEL
CONNECTED COMPONENTS
Oven lamp / Turntable motor
Power transformer
Heating element
Damper motor
Convection motor
Cooling fan motor
3RD STAGE
TIME LEVEL TIME
52sec. 50% 32sec.
G11 G12
HIGH MIX
BROIL
ROAST
4 5
300°F 325°F
9 0
425°F 450°F
START
STOP
CLEAR
4TH STAGE
LEVEL TIME
30% 40sec.