Sharp 902SH, Service Manual

Page: 37 / 121

902SH
2 – 29
CONFIDENTIAL
7. Vibrator does not work.
8. Speaker does not work.
•
When both voice and ring tones are not heard from the speaker, check the items of 8.1.
•
When ring tones are heard from the speaker but voice is not, check the items of 8.2.
•
When voice is heard from the speaker but ring tones are not, check the items of 8.3.
8.1. Both voice and ring tones are not heard from the speaker.
Is 3.0 V on TP1609 when the vibrator is
removed and then activated? At this time, is 1.6 V or more on IC1601 pin 1? IC1600 is defective.
IC1601, CA1609, and D1600 are defective,
mounted improperly, or short-circuited
Is 3.0 V on TP1609 when the vibrator is fixed
and then activated? Vibrator is defective.
The vibrator is defective, or there is clogging
caused by foreign objects.
Is there contact between the FPC land and the
speaker spring? Poor contact.
Is the impedance between speaker terminals
approx.8 ohms? Speaker parts are defective.
Is there conduction between each speaker
FPC land and the corresponding pair (C3004,
C3005, C3010, or C3011)? The speaker FPC is defective or in poor contact
with CN3003.
Does each of R3051, R3052, R3053, and
R3054 have 1 ohm of resistance? R3051, R3052, R3053, R3054, R3000A,
R3001A, R3002A and R3003A are defective.
Is there conduction between R3051/R3052/
R3053/R3054 and the corresponding pair
(TP1608/TP1610/TP1611/TP1612)? The thin coaxial is defective. Otherwise, the
thin coaxial and CN1501 or CN3001 have poor
contact
IC1603, C1632, C1620, R1613, R1614, R1615,
R1616, R1642 and R1646 are defective.
Are signals sent to R1642 and R1646? Is the battery voltage applied to R1656 and
R1624? Also is the voltage 2.9 V applied to
R1645? The main PWB or the
power supply system
is defective.
Are signals sent to C1621 and C1622? Is the battery voltage applied to R1607? Also is
the voltage 1.8 V applied to R1602 and 2.9 V to
R1606 and R1609? IC1600 is defective.
C1621, C1622, C1625, C1626, R1617, R1618,
R1619, R1620, R1631 and IC1600 are defec-
tive. The main PWB or the power supply system is
defective.
NO NO
YES
YES
NO
YES
NO
YES
NO
YES
NO
YES
NO
YES
NO
YES
YES
YES NO
NO
NO YES
YES NO