Troubleshooting Guide - Daewoo KOC-971C0S Service Manual

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 then check continuity with the AC plug removed. To do otherwise may result in a false reading or damage to your meter.
NOTE
W hen electric parts are checked, be sure the pow er cord is not inserted into the w all outlet.
C heck w ire harness, w iring, and connected of the term inals and pow er cord before check parts listed below.
(TROUBLE 1) Oven does not operate at all; any inputs can not be accepted.
CON DITION
Fuse b low s.
fuse and operate the unit
CHECK
C heck continuity of
interlock m onitor sw itch
w ith door closed

(C O M NC )
C heck continuity of both
prim ary and secondary
interlock sw itch w ith
door closed
C heck continuity of
prim ary interlock sw itch
contact with door
partially open until
interlock m onitor sw itch
contact close

(C O M NC close)
C heck continuity of
prim ary w inding of low
voltage transform er
D isconnect high voltage
RESULT CAUSE


(C O M NC )
M alfunction
C ontinuity
of interlock


m onitor
(C O M NC )
N o C ontinuity
N o M alfunction
C ontinuity of interlock
C ontinuity
C ontinuity
S horted
contacts of
prim ary
interlock
Ω or
0 infinite
D efective low
voltage
A pprox.
transfo rm er
150~210
(norm al)
Fuse a gain
D efective
blows
high voltage
transfo rm er


REM EDY
R eplace
N O TE 1
sw itch
R eplace
N O TE 1
sw itch
R eplace
N O TE 1
sw itch
R eplace
R eplace