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R-951M - 7
TOUCH CONTROL
KEY UNIT TEST
If the display fails to clear when the STOP/CLEAR pad is depressed, first verify the flat ribbon cable is marking
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,
disconnecct 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 marking 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.
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,
disconnecct 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 marking 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.
CARRY OUT 4R CHECKS.
TOUCH CONTROL PANEL ASSEMBLY TEST
The touch control panel consists of circuits including semiconductors such as LSI, ICs, etc. Therefore, unlike
conventional microwave ovens, proper maintenance can not be performed with only a voltmeter and ohmmeter.
In this service manual, the touch control panel assembly is divided into two units, Control Unit and Key Unit, and
troubleshooting by unit replacement is described according to the symptoms indicated.
1.
conventional microwave ovens, proper maintenance can not be performed with only a voltmeter and ohmmeter.
In this service manual, the touch control panel assembly is divided into two units, Control Unit and Key Unit, and
troubleshooting by unit replacement is described according to the symptoms indicated.
1.
Key Unit Note : Check key unit ribbon connection before replacement.
The following symptoms indicate a defective key unit. Replace the key unit.
a) When touching the pads, a certain pad produces no signal at all.
b) When touching a number pad, two figures or more are displayed.
c) When touching the pads, sometimes a pad produces no signal.
The following symptoms indicate a defective key unit. Replace the key unit.
a) When touching the pads, a certain pad produces no signal at all.
b) When touching a number pad, two figures or more are displayed.
c) When touching the pads, sometimes a pad produces no signal.
2.
Control Panel
The following symptoms indicate a defective control unit. Before replacing the control unit.
perform the key unit test (Procedure N) to determine if control unit is faulty.
The following symptoms indicate a defective control unit. Before replacing the control unit.
perform the key unit test (Procedure N) to determine if control unit is faulty.
2-1. In connection with pads
a) When touching the pads, a certain group of pads do not produce a signal.
b) When touching the pads, no pads produce a signal.
b) When touching the pads, no pads produce a signal.
2-2. In connection with indicators
a) At a certain digit, all or some segments do not light up.
b) At a certain digit, brightness is low.
c) Only one indicator does not light up.
d) The corresponding segments of all digits do not light up; or they continue to light up.
e) Wrong figure appears.
f) A certain group of indicators do not light up.
g) The figure of all digits flicker.
b) At a certain digit, brightness is low.
c) Only one indicator does not light up.
d) The corresponding segments of all digits do not light up; or they continue to light up.
e) Wrong figure appears.
f) A certain group of indicators do not light up.
g) The figure of all digits flicker.
2-3. Other possible troubles caused by defective control unit.
a) Buzzer does not sound or continues to sound.
b) Clock does not operate properly.
c) Cooking is not possible.
d) Proper temperature measurement is not obtained.
b) Clock does not operate properly.
c) Cooking is not possible.
d) Proper temperature measurement is not obtained.
G11
G7
G2
G5. 9
G12
AUTO
START
CLOCK
AUTO
COOK
AUTO
DEFROST
STOP/
CLEAR
Kg / Lb
Kg • Lb
CHICKEN PORTIONS
BOILED POTATOES
BAKED POTATOES
FRESH FISH
YORKSHIRE PUDDING
RICE / PASTA
OVEN CHIPS
FRESH VEG.
FROZEN VEG.
g • oz
MORE
GRILL
TIMER
LESS
10min.
10sec.
1min.
DUAL
CONVECTION/
GRILL
CONVECTION
TEMPERATURE
MICROWAVE
POWER LEVEL
START
AUTO MINUTE
G10
G8
G6
G4
G1
G3
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