Panasonic NN-F623MF, Руководство по обслуживанию

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SYMPTOM
STEP
CHECK RESULT CAUSE
CORRECTIONS
No display when oven is first
plugged in. Oven is dead. 1 Fuse pattern of DPC Normal STEP 2
Open (NOTE) Shorted
ZNR,L.V.T.,
Lamp
etc.Replace
2 Low voltage
transformer (LVT)
secondary voltage Abnormal 0V LVT
Normal
Step
3
IC-1 pin 16 voltage
(Emitter of Q11)
Abnormal ZD11, Q11
Normal = 5V Display
NOTE
Procedure of fuse pattern repairing is as follows:
1. When the fuse pattern (PF2) opens.
(1) Remove the jumper wire (PF1).
(2) Insert the removed jumper wire (PF1) to “(PF2)” position and solder it. If both “PF1” and “PF2”
patterns are open, replace DPC.
2. When the fuse pattern (PF4) opens.
(1) Remove the jumper wire (PF3).
(2) Insert the removed jumper wire (PF3) to “(PF4)” position and solder it. If both “PF3” and “PF4”
patterns are open, replace DPC.
NOTE:* At the time of these repairs, make visual inspection of the varistor for burning damage and
the transformer with tester for the presence of layer short-circuit (check primary coil resistance).
If any abnormal condition is detected, replace the defective parts.
No key input 1 Membrane switch
continuity Abnormal Membrane
Normal IC-1
No beep sound 1 IC-1 pin 29 voltage Abnormal IC-1
Normal BZ, Q224
Power relay A(RY-2) does not
turn on even though the
program has been set and the
start pad is tapped 1 IC-1 pin 9 voltage
while operation Abnormal IC-1
Normal = 5V
Step
2 Short circuit between
collector and Emitter
of Q223. Still does not turn on RY-2
RY-2 turns on Q223
No microwave oscillation at
any power setting 1 IC-1 pin 7 and pin 34
voltages while
operation at high
power Abnormal IC-1
Normal
Step
7---5V
2 Q220 transistor Abnormal Q220
Normal RY-1
Dark or unclear display 1 Replace display and
check operation Normal DISPLAY
Abnormal IC-1
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