LG MB-3071MC Service Manual page 21

COMPONENTS
HEATER ELEMENT
(Wire leads removed.)
MAGNETRON
THERMOSTAT
OVEN
THERMOSTAT
FUSE
(Wire leads removed.)
TEST PROCEDURE
Measure the resistance.
(Multi-meter scale:RX1)
Measure the resistance with 500V-100M
Ohm insulation resistance meter.
NOTE: Make sure heater is fully cooled when tested.
Check the continuity of the switch
with an Multi-meter
NOTE: If the fuse is blown, check primary, the secondary, the monitor
switches, H.V.D and H.V.C before replacing the fuse.
If the fuse is blown by improper switch operation replace the defective
switch and the fuse at the same time.
Replace just the fuse if the switches operate normally.
5-11
RESULTS
Normal:
Gill heater
Approx.55 Ω
(at 20-30˚C)
Normal:
more than 0.5M Ω
0˚C~Approx 180˚C Approx 180˚C
0˚C~Approx 145˚C Approx 145˚C
Normal Abnormal