LG MV1825SW - Manual (Page 30)

7-19
(2) CHECKOUT PROCEDURES FOR RELAY.
- PROBLEM (A) -
FAN motor and oven lamp turn on without touching
START key when the door is closed.
Remove the mate connector of I/O
CON from the circuit board.
Does the unit still operate?
GOOD
Replace the
circuit board
Replace
RELAY1
- PROBLEM (B) -
FAN motor and oven lamp turn on When the door is
closed and START key is touched.
Measure the voltage at pin NO.
35 of U01
Voltage reading: 0 Vdc
10 of U03
Voltage reading: about 15V
Replace the
circuit board
Defective
RELAY1 or poor
connection of
RELAY1
Defective
RELAY1
Replace
RELAY1 or correct
the connection.
NO
NO
YES
YES
NO
NO
YES
YES
GOOD