Troubleshooting - Panasonic Microwave Ovens with Inverters Technical Manual

Troubleshooting

Symptom
Oven is dead.
Fuse is ok.
1
No display and no operation
at all.
No display and no operation
2 at all.
Fuse is blown
The Oven does not accept
3
key input (Program)
The Oven lamp and the fan
4 motor turn on when oven is
plugged in with door closed.
Timer starts to countdown,
but there's no microwave
5 oscillation. (No heat while the
oven lamp and the fan motor
are on)
Troubleshooting table
Cause
1. Open or loose wire harness
2. Open Thermal cutout.
3. Open low voltage transformer.
4. Defective DPC
1. Shorted harness.
2. Defective primary switch
3. Defective the short switch.
4. Defective Inverter Power supply
1. Defective DPC
2. Open or loose connection of the membrane keypad.
3. Shorted or open membrane keyboard.
1. Misadjusted secondary switch or loose wiring.
2. Defective secondary switch
1. Switches alignment is off
2. Open or loose connection of high voltage circuit,
especially the magnetron filament circuit.
3. Defective Inverter
4. Defective magnetron
5. Open or loose wiring of power relay B.
6. Defective primary switch.
7. Defective power relay B or DPC
31
Corrections
Check the fan motor
when the cutout is
defective.
Check adjustments of
primary switch,
secondary switch, and
short switch
Adjust door and latch
switches
Adjust door and latch
switches.
Check the Magnetron
and the Inverter.