LG LRG4111ST Service Manual page 67

F3 error (Button short error)
Or button does not input
Unplug the unit
1
Check the connecting states
between Touch PCB and
CN53 of Main PCB.
Is it OK?
TROUBLE SHOOTING
Reconnect
No
or adjust the
connection
CN53
Yes
Plug in the unit
2
Replace the Control panel.
(With Glass Touch PCB)
And then check button operation
using key test mode
To enter the test mode, follow these steps:
(1) press the CLEAR button
(2) press the BAKE and
BROIL buttons at the same time
(3) press the BAKE and
BROIL buttons at the same time again.
(4) press the NUM 7 button
(5) Check the button.
(Refer to the next page, appendix)
If button is not operated,
3
Replace the Main PCB
8-20