Daewoo KOR-1N4A9W, Service Manual, Page: 18 / 34

17
(TROUBLE 1) Oven does not operate at all ; any inputs can not be accepted.
TROUBLESHOOTING GUIDE
CONDITION CHECK
Check continuity of interlock
monitor switch with door closed
Check continuity of primary
inter-lock switch contact with
door partially open until
interlock mon-itor switch
contact close (COM
↔
NC)
Malfunction of
interlock moni-
tor switch
Shorted con-
tacts of primary
interlock switch.
RESULT
Continuity
No Continuity
No Continuity
CAUSE REMEDY
Replace
Fuse blows.
Replace
Defective low
voltage
transformer
0 Ω or infinite
Approx.
1500~1850
(normal)
Replace
Check continuity of primary
winding of low voltage
transformer
Defective low
voltage trans-
former
Fuse again
blows
Replace
Disconnect high voltage fuse
and operate the unit
Continuity
Check continuity of both primary
and secondary interlock switch
with door colosed
Malfunction of
interlock switch
Continuity
Replace No Continuity
Following the procedure below to check if the oven is defective or not.
1. Check grounding before trouble checking.
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 check continuity with the AC plug removed. To do otherwise may result in a false reading or damage to your meter.
NOTE : When electric parts are checked, be sure the power cord is not inserted the wall outlet.
Check wire harness, wiring and connected of the terminals and power cord before check the parts listed
below.