Panasonic 1200 watt microwave oven model:NN-S561BF,year:May 2001.When
trying to heat foods the unit runs for 5-10 seconds then stops,I don't
sense any heat.Anyone have any common repair tips? as I have stopped
repairing microwave ovens along time ago as most of the ones I came
across had defective flyback transformers I meant magnetrons.
Sidney
Dartmouth,Nova Scotia
Canada
that microwave uses an inverter board that may need to be serviced
check the following
DB701
D701, D702
Q701, Q702
It's recommended to use an AC line input current Ampere meter and 1
litre of water load for testing
· Program DPC: press CLOCK, TIMER, START, POWER pad
· Unplug HV lead wire connector CN703 from inverter
· Program oven for 1 minute and press START
· After approximately 23 seconds, oven displays H98 and stops
· Confirm the input current is 0.8A to 1.7A during 23 seconds
operation
· Press RESET pad
· Unplug CN701 (4A0; 4T0)
· Program oven for 1 minute and press START
· After approximately 3 seconds, oven displays H97 and stops
· Confirm the input current is 0.4A to 0.8A during 3 seconds
operation
If the above test is satisfied, the Inverter can be determined OK
2. A606Y4T00CP Check point:
· Visual checking: R710, R711, C703 burnt
· VOM test: D701, D702, DB701 and Q702, Q701 (replace both Q701 &
Q702), ZD703, ZD704 shorted
Note: Replace a short jumper at R713 location by a 4.7 ohm resistor to
prevent
R710, R711 from burning and correct R710, R711 value from 39 ohm to 30
ohm
Symptom Check
Shuts down after few seconds Q701, Q702, DB701, D701, D702, ZD703,
ZD704,
R710 / R711 (burnt), R713 (opened)
Low or Fluctuating input current
C703 (crack, leakage), D710, CT701
Mini PCB
Hissing sound C703, R713 (opened),
CT701 (secondary opened)
Shrieking sound at start up L701
