Sharp GX15, Service Manual

Page: 56 / 122

GX15
2 – 48
CONFIDENTIAL
3. No voice is heard from the earpiece.
Phone (Handset)
Do keypad tones and melodies sound? Go to the section “Earpiece (for loud speaker) does not work”.
(see page 2-50)
Is 0.5 V or more applied to R101 (IC103 pin 9 side)? IC103 is defective.
Is 0.5 V or more applied to JK101 pin 5? Parts between socket JK101 pin 5 and IC103 pin 9 are defec-
tive.
Is 0.5 V or more applied to JK101 pin 3? Socket JK101 is defective.
Is 0.5 V or more applied to TP120? Parts between socket JK101 pin 3 and TP120 are defective.
Is 2.4 - 2.6 V applied to TP176? R122 is defective.
Is 2.4 - 2.6 V applied to R115 (IC103 pin 76 side)? R115 is defective. (Hands free kit mode is set.)
IC103 is defective.
Hands free kit (Headset)
Replace the hands free kit. Is sound produced? The hands free kit is defective.
Is signal sent to JK101 pin 4? Socket JK101 is defective, or the hands free kit is in a poor
contact with the socket plug.
Is signal sent to TP121? Parts between socket JK101 pin 4 and TP121 are defective.
Is signal sent to R124 (IC103 pin 60 side)? Parts between IC103 pin 60 and TP120 are defective.
Disconnect the hands free kit. Is voice heard in phone mode? IC103 or IC106 is defective.
Is the voltage 0 V on R101 (IC103 pin 9 side)? IC103 is defective.
Socket JK101 is defective.
NO
YES
YES
NO
YES
NO
YES
NO
YES
NO
YES
NO
YES
NO
YES
NO
YES
NO
YES
NO
YES
NO
NO
YES
YES
NO