SYMPTOMS
CAUSE
CORRECTIONS
13
9. TROUBLESHOOTING GUIDE
9.1 (TROUBLE 1) Oven does not start
CAUTION
1. Check the unit is grounded before commencing any troubleshooting.
2. Do not take measurements in the high voltage circuit.
3. Discharge the high voltage capacitor.
4. When checking then continuity of the switches or the high voltage transformer, 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.
5. Do not touch any parts of the circuitry on the digital programmer circuit, since static electric discharge may dam-
age this control panel. Always connect yourself to ground to discharge any static from your body.
Ensure you are touching the ground while working on this panel to dischage any static charge in your body.
6. 230VAC is present in the shaded area of the digital programmer circuit board (Terminals of power relays and
primary circuit of low voltage transformer). Beware of electric shock.
First of all operate the oven by following the operation procedures exactly in order to find the symptom.
1
Oven is dead.
Fuse is OK.
No display and no operation
at all
2
Oven does not accept key
input (program).
3.
Oven lamp and turntable
motor turn on when oven is
plugged in with door closed.
4
Timer starts countdown but no
microwave oscillation.
1. Open or loose lead wire harness.
2. Open oven thermostat.
3. Open low voltage transformer.
4. Defective DPC.
1. Key input is not in sequence.
2. Open or loose connection of mem-
brane keypad to DPC(Flat cable)
3. Shorted or open membrane key-
board.
4. Defective DPC.
1. Misadjustment or loose wiring of
secondary latch switch.
2. Defective secondary latch switch.
1. Off-alignment of latch switches.
2. Open primary latch switch.
3. Open or loose wiring of power
relay 1 (RY1).
4. Defective power relay 1 (RY1).
5. Defective DPC.
6. Open or loose connection of high
voltage circuit especially mag-
netron filament circuit.
NOTE: Large contact resistance will
bring lower magnetron fila-
ment voltage and cause
magnetron to have lower out-
put and/or be intermittent.
7. Defecitive high voltage componet:
H.V.Transformer
H.V. Capacitor
H.V.Diode
Magnetron
Check fan motor when oven ther-
mostat is defective.
Refer to operation procedure.
Refer to DPC troubleshooting.
Adjust door and latch switches.
Adjust door and latch switches.
Check high voltage component
according to component test pro-
cedure and replace if it is defec-
tive.
NEW H.V.
