Daewoo KQG-868G7S, Service Manual

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3. When there is no microwave oscillation
1) When touching START button, oven lamp does not turn on.
Fan motor do not rotate, but cook indicator in display comes on.
✻
Cause : RELAY 2 does not operate.
→
refer to Circuit Diagram (point 3)
- Check method
2) When touching START button, oven lamp turns on.
Fan motor and turntable rotate and cook indicator in display comes on.
✻
Cause : RELAY 1 does not operate.
→
refer to Circuit Diagram (point 2)
- Check method
4. When there is no grill oscillation.
✻
Cause : RELAY 3 does not operate.
→
refer to Circuit Diagram (point 6)
- Check method
5. When the door is opened during operation, the count down timer does not stop.
→
refer to Circuit Diagram (point 1)
- Check method
6. When the digital clock does not operate properly.
→
refer to Circuit Diagram (point 5)
POINT
A B
STATE
RELAY 2 ON -5VDC GND
RELAY 2 OFF GND -12VDC
POINT
A B
STATE
RELAY 1 ON -5VDC GND
RELAY 1 OFF GND -12VDC
POINT
A B
STATE
RELAY 3 ON -5VDC GND
RELAY 3 OFF GND -12VDC
POINT
A B
STATE
1) DOOR OPEN OPEN -5VDC
2) DOOR CLOSED CLOSE GND
CHECK NO HETHOD REMEDY
1 Check the stage(ON, OFF) of the door open monitor Replace door open monitor switch.
switch by resistance measurement.
POINT WAVE FORM
A
T: 20 ms(50Hz)
❈
If clock does not keep exact
time, you must check resis-
tor R13,14, zener diode
ZD1.