Buzzer Driving Circuit; Door Opening Sensing Circuit - LG GR-B207WVQ.CSWQAGE Service Manual

EXPLATION FOR MICOM CIRCUIT

2.Buzzer driving circuit

CONDITIONS
MEASURING
POINTS
IC1 (No. 50 Pin)
IC1 (No. 50 Pin)

3.Door opening sensing circuit

Door of Freezing/Cold Storage Room
Closing
Opening
Since door switch sensing switch (A), (B) are a separate switch even if the door switch of the freezing room normally
operates, they may fail to sense door opening in the failure of switch at both ends of (A) and (B) or in failure of the L/wire.
Lamp does at the cold storage room not turn on if the door switch of the cold storage room fails to sense the door open
switch (c ), (d) or the home bar switch(e ), (f).
Bell sounds when button on
dosplay is pressed.
0.05 s 0.2 s 0.1 s
5 V
0 V
5 V
0 V
2.63 kz (DING) 2.21 kz (DONG)
Measuring part
Beep sounds when warning
0.4 s
5 V
0 V
5 V
0 V
2.63 kz (BEEP)
IC1 (MICOM) No. 47, 46 Pin
,
5 V ( A - B , C - D . E - F
0 V ( A - B , C - D ,
,
E - F
- 16 -
door opening.
0.5 s 0.5 s
OFF
S/W at both ends are at Off status)
S/W at both ends are at On status)
OFF
0 V
0 V