8 – 4
[8] H: KEY UNIT (MEMBRANE SWITCH) TEST
1. CARRY OUT 3D CHECKS.
2. 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 2nd.
Interlock relay control switch operates properly; that is the contacts are closed when the door is closed and open when the door is open.
3. If the 2nd. Interlock relay control switch is good, disconnect the flat ribbon cable that connects the key unit to the control unit and make sure the
2nd. interlock relay control switch is closed (either close the door or short the 2nd. interlock relay control switch connector).
4. Disconnect the leads to the primary of the inverter unit.
5. Ensure that the leads remain isolated from other components and oven chassis by using insulation tape.
6. After that procedure, reconnect the power supply cord.
7. 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 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 keypad is at fault.
8. CARRY OUT 4R CHECKS.
[9] I: PROCEDURES TO BE TAKEN WHEN THE FUSE F1 ON THE PRINTED WIRING BOARD
(PWB) IS OPEN
To protect the electronic circuits, this model is provided with the FUSE F1 added to the primary on the PWB. If the FUSE F1 is open, follow the trou-
bleshooting guide given below for repair.
CARRY OUT 3D CHECKS.
NOTE: *At the time of making these repairs, make a visual inspection of the varistor. Check for burned damage and examine the transformer with a
tester for the presence of layer short-circuit (check the primary coil resistance). If any abnormal condition is detected, replace the control unit.
CARRY OUT 4R CHECKS.
[10] J: HUMIDITY SENSOR TEST
Checking the initial sensor cooking condition
WARNING: The oven should be fully assembled before following procedure.
1) The oven should be plugged in at least two minutes before sensor cooking.
2) Room temperature should not exceed 95 F (35 C).
3) The unit should not be installed in any area where heat and steam are generated. The unit should not be installed, for example, next to a conven-
tional surface unit. Refer to the “INSTALLATION INSTRUCTIONS” of the operation manual.
4) Exhaust vents are provided on the back of the unit for proper cooling and air flow in the cavity. To permit adequate ventilation, be sure to install so
as not to block these vents. There should be some space for air circulation.
5) Be sure the exterior of the cooking container and the interior of the oven are dry. Wipe off any moisture with a dry cloth or paper towel.
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P
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1
The rated AC voltage is not present primary side of low voltage transformer.
Check supply voltage and oven power cord.
2
The rated AC voltage is present to primary side of low voltage transformer.
Low voltage transformer or secondary circuit defective.
Replace the control unit.
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< KEY UNIT >
31
32
36
35
34
33
37
38
G1
G2
G3
G4
G5
G6
G7
G8
G9
G10
G11
G12
(G13)
EASY
DEFORST
SENSOR
REHEAT
INFO
TIMER
3
2
1
6
5
4
7
8
9
0
POWER
LEVEL
LESS
RICE
PASTA
STOP
CLEAR
FRESH
VEGETABLES
MORE
QUICK
MEALS
JACKET
POTATO
FROZEN
VEGETABLES
EASY
MEALS
EXPRESS
DUNNER PLATE
MELT
SOFTEN
INSTANT COOK
START
39
40
41
42
43
R-350Y(S)
