Daewoo KOT-1G1A, Service Manual, Page: 29 / 58

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TROUBLE SHOOTING GUIDE
Following the procedures below to check if the oven is defective or not.
1. Check grounding before checking trouble.
2. Be careful of the high voltage circuit.
3. Discharge the high voltage capacitor.
4. When checking the continuity of the switches, fuse or high voltage transformer, disconnect one lead wire from these parts
and the 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 part of the circuit on the touch control 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 built up in your body.
First of all, operate the microwave oven following the correct operation described in users guide manual (instruction
manual) by time cooking in order to find the exact cause of any trouble.
(TROUBLE 1) Oven does not operate at all; any input can not be accepted.
CONDITION CHECK
Check continuity of
interlock monitor
switch with door
closed
Check continuity of
primary interlock
switch contact with
door partially open
until interlock
monitor switch
contact close
Malfunction of
interlock monitor
switch
RESULT
continuity
No Continuity
CAUSE REMEDY
Replace
(NOTE1)
(NOTE1)
Replace fuse
Fuse blows
Shorted contacts
of primary
interlock switch
continuity Replace
Check continuity of
primary winding of
low voltage
transformer
Disconnect one
side of the lead
wire connected
from high voltage
Transformer to
high voltage
Capacitor and
operate the unit
Defective low
voltage
transformer
0 or infinite
Approx.150~310
(normal)
Defective high
voltage capacitor
Defective low
voltage transformer
Normal
Fuse again blows
Replace
Replace
Replace