LG MH-654S Service Manual page 27

(TROUBLE 6) Oven does not cook properly when programmed for the set power level
(Operates properly on HIGH)
CONDITION
Output is full when
you set lower
power level.
(TROUBLE 7) Grill
CONDITION
1. Heater is not
operating.
1. Lower tempera-
ture the oven.
NOTE: * Make sure the wore leads correct position.
* When removing the wire leads from parts be sure to grasp the connector not the wires.
* When removing the magnetron, be sure to install the magnetron gasket in the correct position and in
good condition.
CHECK
Disconnect the
wire leads from
relay 2 and check
continuity relay 2.
(Operate the unit)
CHECK
Heater.
Thermostat and
relay3.(Grill)
Wire connection.
Heater.
Thermostat and
relay3.(Grill)
RESULT
Abnormal.
RESULT
Abnormal.
Normal.
Abnormal.
Normal.
No continuity.
Abnormal.
Normal.
Abnormal.
5-17
CAUSE
Defective P.C.B.
assembly.
CAUSE
Malfunction the
heater.
Malfunction the
thermostat.
Open or loosen.
Malfunction the
heater.
Malfunction the
thermostat.
REMEDY
Replace P.C.B.
assembly.
REMEDY
Replace.
Replace.
Replace or
connect tightly.
Replace.
Replace.