LG LRBN2051 Series, Service Manual

Page: 23 / 50

2. Buzzer Drive Condition Check
3. Open Door Detection Circuit Check
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OFF
IC1 ( ) 0 V
IC1 ( ) 0 V
Measure-
ment Location
Condition
0 V
5 V
0 V
5 V
0.5 s 0.5 s
2.63 kz (Beep~) OFF
0.05 s 0.1 s 0.2 s 2 s
0 V
5 V
0 V
5 V
2.63 kz (Ding~) 2.21 kz (Dong~)
(PIN NO.31 & PIN NO.30)
Closed 5 V
Open 0 V
Freezer/
Refrigerator Door
Measurement
Location
A
B
Tone (Ding~Dong~) when the button on
the display is pushed.
Alarm for open door
(beep-beep-beep)