Casio SF-8500 Service Manual & Parts List page 32

2
Connection of keyboard cable OK?
Yes
When press power on Key, any
oscillation at oscillator?
Yes
Pin 45 of HD62076C02 "H" ?
Yes
Pin 31 of µPD65005G-566-3B6 "H" ?
Yes
Pin 32 of µPD65005G-566-3B6 "H"
?
Yes
No
Pin 31 of SC371015FU "H" ?
Yes
Pin 39 of µPD65005G-566-3B6 "L" ?
Yes
No
Pin 3 of transistor Q1 "H" ?
Yes
Pin 1 and 32 of ROM µPD23C4001EBGW-304 "+4.5V" ?
Yes
Pin 32 of ROM µPD23C4001EBGW-304 "Pulse" ?
Yes
Poor connection on ROM, RAM or CPU ?
No
No
Adjust keyboard cable.
No
Poor connection
on oscillator?
No
Poor connection?
No
No
Poor connection?
Poor connection?
No
Poor connection?
Poor connection?
No
No
Poor connection
on ROM or CPU?
Yes
Replace ROM, RAM or CPU.
— 31 —
Yes
Solder line
No
Replace parts.
Yes
Solder line
No
Replace parts.
Solder line
Yes
Solder line
No
Replace parts.
Solder line
Yes
Solder line
No
Replace parts.
Yes
Solder line
No
Replace parts.
Solder line
Yes
Solder line
No
Replace CPU.
Solder line
1
1
1
1
1
1
1
1
1
1
1