Read Panasonic NN-S453WF / NN-S553WF / NN-K593MF / NN-K573MF / NN-K573WF / NN-K543WF Service Manual online
9 TROUBLESHOOTING GUIDE
DANGER HIGH VOLTAGES
1. DO NOT RE-ADJUST PRESET CONTROL on the H.V.Inverter (U). It is very dangerous to repair or adjust without sufficient test equipment
because this circuit handles very large current and high voltage. Operating a misaligned inverter circuit is dangerous.
2. Ensure proper grounding before checking for trouble.
3. Be careful of the high voltage circuitry, taking necessary precautions when troubleshooting.
4. Discharge high voltage remains in the H.V.Inverter (U).
5. When checking the continuity of the switches or the H.V.Inverter, disconnect one lead wire from these parts and then check continuity with the
3. Be careful of the high voltage circuitry, taking necessary precautions when troubleshooting.
4. Discharge high voltage remains in the H.V.Inverter (U).
5. When checking the continuity of the switches or the H.V.Inverter, disconnect one lead wire from these parts and then check continuity with the
AC plug removed. To do otherwise may result in a false reading or damage to your meter. When disconnecting a plastic connector from a
terminal, you must hold the plastic connector instead of the lead wire and then disconnect it, otherwise lead wire may be open or the connector
cannot be removed.
terminal, you must hold the plastic connector instead of the lead wire and then disconnect it, otherwise lead wire may be open or the connector
cannot be removed.
6. Do not touch any parts of the circuitry on the digital programmer circuit, since static electric discharge may damage this control panel. Always
touch yourself to ground while working on this panel to discharge any static charge in your body.
7. 230-240V AC is present on the digital programmer circuit (Terminals of power relay’s and primary circuit of Digital Programmer Circuit). When
troubleshooting, be cautious of possible electrical shock hazard.
Before troubleshooting, operate the microwave oven following the correct operating procedures in the instruction manual in order
to find the exact cause of any trouble, since operator error may be mistaken for the oven’s malfunction.
to find the exact cause of any trouble, since operator error may be mistaken for the oven’s malfunction.
9.1. (Trouble) Oven stops operation during cooking
SYMPTOM
CAUSE
CORRECTIONS
1.
Oven
stops
in
3
seconds
after
pressing start pad
No 230-240V AC is supplied to H.V.Inverter (U)
CN702 terminals
CN702 terminals
1. Latch Switch
2. Power relay RY-1
3. Loose lead wire connector CN701, CN702
2. Power relay RY-1
3. Loose lead wire connector CN701, CN702
Oven
stops
in
23
seconds
after
pressing start pad
H.V.Inverter (U) operates by the control signals
from DPC but magnetron is not oscillating
from DPC but magnetron is not oscillating
1. Magnetron
2. Loose lead wire connector CN703
2. Loose lead wire connector CN703
Oven
stops
in
10
seconds
after
pressing start pad
(Auto sensor cooking)
(Auto sensor cooking)
Steam sensor circuit does not function
1. Steam sensor
2. DPC
3. Loose wiring connector CN2
2. DPC
3. Loose wiring connector CN2
2.
No display and no operation at all.
Fuse is blown.
Fuse is blown.
Most probably loose connection of connectors or
door latch mechanism is not adjusted properly
door latch mechanism is not adjusted properly
1. Allign door, Door Latch Switches
2. Loose wiring connectors
2. Loose wiring connectors
19
NN-S453WF
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