LG LMV1976ST Service Manual page 28

COMPONENTS
TOUCH KEY
BOARD
SENSOR
(For sensor model only)
TEST PROCEDURES
Measure the resistance between terminal
pins of connector KEY CONNECTOR.
NOTE:
When reconnecting the FPC connector,
make sure that the holes on the FPC
connector are properly engaged with hooks
on the plastic fastener.
MATRIX CIRCUIT FOR
TOUCH KEY BOARD
CONNECTOR(KEY CON)
Figure 27
Figure 29
Resistance
Normal: Approximately
BK~RD: 4.5~6.2 Kohm
RD~WH: 2.0~3.5 Kohm
1 BK
BK~WH: 2.0~3.5 Kohm
2 RD
3 WH
Abnormal: Infinite or several.
7-17
RESULTS
When
touched
value
Less than More than
400 ohms 1 mega ohm
FPC CONNECTOR
Top
Figure 28
When not
touched
1
2
3
4
5
6
7
8
9
10
11
12
13