Casio SF-5300B Service Manual & Parts List page 18

No/Erratic display
START
Are the power of batteries strong enough?
Is input Pin 2 of REG1 6 V?
Is output Pin 3 of REG1 5.3 V?
Are the voltages of V1, V2, V3, and V4
strong enough?
V1: 1.3 V
V2: 2.5 V
V3: 2.7 V
V4: 3.9 V
Is the soldering of LSI1 poor?
Replace LSI1.
High current consumption
START
Is there any short circuit on the PCB
assembly ?
Are the capacitors C8, C9, C11, C12,
and C13 OK?
Replace the capacitor(s).
Y
Y
Y
Note:
Contrast: Maximum
Y
N
N
N
— —
17
N
Replace the batteries.
N
Adjust the contact and clean
the battery springs.
N
Replace REG1.
N
Replace C1, C2, C3, or C4.
Y
Resolder.
Y
Repair shorts.
Y
Resolder or replace LSIs and ICs.