Daewoo KOC-9N2T7S Service Manual

Contents

Daewoo KOC-9N2T7S Service Manual Manual pdf 21 page image

208. TROUBLE SHOOTING GUIDEFollowing 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 tranformer, disconnect one load wire from theseparts and check continuity with the AC plug removed. To do otherwise may result in a false reading or damage toyour meter.(TROUBLE 1) Oven does not operate at all : any inputs can not be accepted.NOTE : When electric parts are checked, be sure the power cord is not inserted the wall outlet.Check wire harness, wiring and connection of the terminals and power cord before check the parts listed below.CONDITION CHECKCheck continuity ofinterlock monitor switch withdoor closed( COM NC )Check continuity ofboth primary and secondaryinterlock switch with door closedMalfunction ofInterlockmonitor switchMalfunction ofinterlock switchRESULTContinuityNo continuityCAUSE REMEDYReplace(COM NC)Fuse blows.ReplaceShorted contactsof primaryinterlock SwitchContinuity ReplaceCheck continuity ofprimary interlock switch contactwith door partially open untilinterlock monitor switch contactclose( COM NC close )Defective lowvoltagetransformerDefectivehigh voltagetransformeror infinite ReplaceReplaceCheck continuity ofprimary winding of low voltagetransformerDisconnect high voltagefuse and operate the unitNoContinuityContinuityApprox.480 ~620( normal )Fuse againblows