LG MC2841SPS, Service Manual

Page: 20 / 39

5-10
COMPONENTS TEST PROCEDURE RESULTS
FUSE
HEATER ELEMENT
(Wire leads removed.)
MAGNETRON
THERMOSTAT
Check for continuity of the fuse with an
multi-meter.
NOTE: If the fuse is blown, check the primary, the secondary, and 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.
NOTE: Make sure heater is fully cooled when tested.
Measure the resistance.
(Multi-meter scale: Rx1) Normal:
*Grill heater
Approx. 42 ohm
(at 20 ~ 30
o
C)
*Convection heater
Approx. 63 ohm
(at 20 ~ 30
o
C)
Normal: more than 0.5 Mohm
Normal Abnormal
Measure the resistance with 500V-100M ohm
insulation resistance meter.
0°C~Approx.60°C Approx.60°C
0°C~Approx.145°C Approx.145°C
CONVECTION
THERMOSTAT