Hook Switch Not Working; Melody Not Ringing - Pantech G800 Service Manual

G800 Service Manual

6.2.5 Hook Switch not working

1.Check to see if U111 No.5 is 2.8V : CP123
2.Check to see if U111 No.1 is 0V during pressing Hook Switch : CP124
3.Check to see if U111 No.3 is around 0.15V : CP125
NO Check that R109 and R110 cold solder,broken,short to the other
PCB pattern or not
If you find out any defect, you replace it
4.Check to see if U111 No.4 is around 0V When you press Hook Switch : CP126
NO Check that U111 or R109 cold solder,broken,short to the other
PCB pattern or not
If you find out any defect, you replace it

6.3. 6.2.6 Melody not ringing

1.Check to see if U105.7 , 32 is 2.8V_EXT : CP127
2.Check to see if U105.15 is Vbat : CP128
3.Check U105.Nos 12, 13 and 14 pin for wave form : CP129
NO Check that R175, R177, R131, C196, C197 cold solder,broken,short to the other
PCB pattern or not
If you find out any defect, you replace it
4.Check SPK No. SPOUT1 and SPOUT2 for wave form : CP130
NO Replacd SPK
PANTECH
CP123
`
CP124
`
CP125
`
CP126
`
CP123
CP124
CP125
CP126
- 35 -
R&D CONFIDENTIAL