Sharp 902SH Service Manual page 37

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