WAVEJET MICROWAVE OVEN
COMPONENT MAINTENANCE MANUAL
WITH ILLUSTRATED PARTS LIST
25-30-43
Page
104
March 15, 2003
Symptom
Fault Isolation
Display is active, +/- respond, counts down
when “Start” is pressed. Turntable does
not turn and microwave does not heat.
A.
Check magnetron thermostat to see
if it is open.
B.
Verify cabin altitude is less than
9,000 feet.
C.
Check altitude switch.
D.
Check for controller card failure.
Display is active, +/- respond, counts down
when “Start” is pressed. Turntable does
not turn and microwave heats.
A.
Check for inverter board failure.
B.
Check for turntable motor failure.
Display is active, +/- respond, counts down
when “Start” is pressed. Turntable turns
and microwave does not heat.
A.
Check for relay failure.
B.
Check for noise filter failure.
C.
Check for power supply or
magnetron failure.
Display is active, +/- respond, counts down
when “Start” is pressed. Turntable turns
and microwave heats. Lamps do not light.
Lamps have burned out and need to be
replaced. TIA recommends that the lights
be replaced in sets.
Liner or Magnetron thermostat opens
frequently.
A.
Check that microwave installation
allows for adequate fan ventilation.
B.
Check for power output.
WARNING
ALWAYS HAVE TWO PEOPLE PRESENT DURING TESTING. NEVER PROBE HIGH
VOLTAGE.
CAUTION: Always have a load inside the microwave when operating (a cup of
water). A load is necessary to absorb the microwave energy. Operating
an empty oven can cause significant damage to the oven. Always verify
water has not evaporated during testing.
FAULT ISOLATION TABLE
Test
Component
From
To
Result
Action
Taken
Line Side Load Side
<100 OHM
Filter (with Power
Disconnected)
Filter, Between Line
Terminals
>1000 OHM
If any of these are not
met, filter must be
replaced.
Relay Pair (cover
off, 500 ml of water
in oven cavity)
NOTE: TIA recommends that the relays be replaced in pairs, as
they operate in tandem. Relays should wear out at approximately
the same time.
