Service manual

26
3. When there is no microwave oscillation
1) When touching Start/+30sec. pad, oven lamp does not turn on.
Fan motor do not rotate, but cook indicator in display comes on.
- Check method
2) When touching Start/+30sec. pad, oven lamp turns on.
Fan motor and turntable rotate and cook indicator in display comes on.
- Check method
4. When the door is opened during operation, the count down timer does not stop.
-Check method
5. When the digital clock does not operate properly.
→ refer to Circuit Diagram
* If clock does not keep exact time, you must check resistor R20 and zener diode ZD2.
STATE
POINT
AB
RELAY 2 ON 5VDC GND
RELAY 2 OFF GND 15VDC
STATE
POINT
AB
RELAY 1 ON 5VDC GND
RELAY 1 OFF GND 15VDC
STATE
POINT
AB
1) DOOR OPEN OPEN 5VDC
2) DOOR CLOSED CLOSE GND
CHECK NO METHOD REMEDY
1 Check the stage (ON, OFF) of the door open monitor switch by Replace door open monitor
resistance measurement. switch.
POINT WAVE FORM
IC 1 PIN 8
B
A
RY2
RY2
(TRAY
LAMP)
Q10
42
D10
RY1
(M/W)
41
D8
B
A
RY1
Q9
CN1
1
2
C1
+5V
R9 C2
27
R1
R10
D.O.M SW
A B
T
T: 20ms (50Hz)
5V
0V