LG LTRM1240SW Service Manual page 23

(2) CHECKOUT PROCEDURES FOR RELAY.
Microwave Oven
- PROBLEM (A) -
FAN motor and oven lamp turn on without touching
START key when the door is closed.
NO
Remove the mate connector of I/O
GOOD
CON from the circuit board does
the unit still operate?
- PROBLEM (B) -
FAN motor and oven lamp turn on When the door is
closed and START key is touched.
YES
GOOD Check the interlock switches
Replace the
micro switches.
YES
NO
Replace the
circuit board
NO
NO YES
Defective
RELAY or poor
connection of
relay
Replace
RELAY or correct
the connection.
Toaster
FAN motor and indicator light turn on without touching
START key when the door is closed.
NO
GOOD
FAN motor and indicator light turn on When the door
is closed and START key is touched.
YES
GOOD
Replace the
micro switches.
-22-
- PROBLEM (A) -
YES
Remove the mate connector of I/O
CON from the circuit board does
the unit still operate?
NO
Replace the
circuit board
- PROBLEM (B) -
NO
Check the interlock switches
NO
Defective
RELAY or poor
connection of
relay
Replace
RELAY or correct
the connection.
YES