LG LMV1625W Service Manual page 30

(2) CHECKOUT PROCEDURES FOR RELAY.
TT motor and oven lamp turn on without touching
START key when the door is closed.
NO
GOOD
Replace the
circuit board
- PROBLEM (A) -
YES
Remove the mate connector of I/O
CON from the circuit board.
Does the unit still operate?
NO
Defective
RELAY3
YES
RELAY3
Replace
TT motor and oven lamp turn on When the door is
closed and START key is touched.
YES
GOOD
Replace the
circuit board
7-19
- PROBLEM (B) -
NO
Measure the voltage at pin NO.
4 of U01
Voltage reading: 0 Vdc
NO
Defective
RELAY3 or poor
connection of
RELAY3
Replace
RELAY3 or correct
the connection.
YES