LG LRG3091ST Service Manual page 79

CHECKING FLOW CHART BY FAILURE
Oven too hot error F-6 error
No
Normal?
Yes
Replace the power PCB
END
Check the broil relay damage
(measure the resistance)
Welded Normal
Continuity Infinite
No
Normal?
Replace the power PCB
Yes
END
Replace the main PCB
END
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