Specifications

— 30 —
Connection of keyboard cable OK?
2
Replace parts.
Poor connection? Solder line
Replace parts.
Yes
1
Solder line
Poor connection?
Solder line
No
Replace parts.
Yes
1
Poor connection?
Solder line
Adjust keyboard cable.
1
Solder line
Yes
When press power on Key, any
oscillation at oscillator?
Poor connection
on oscillator?
Pin 45 ofµPD3055GF002-2BA "H" ?
Pin 29 of µPD65005G-452-22 "H" ?
Pin 30 of µPD65005G-452-22 "H" ?
Pin 31 of SC371015FU "H" ?
1
Yes
Yes
Yes
Yes
Yes
Solder line
No
Replace parts.
Yes
1
Pin 35 of µPD65005G-452-22 "L" ?
Poor connection?
Solder line
No
Replace parts.
Yes
1
Pin 3 of transistor Q1 "H" ?
Pin 32 of ROM µPD23C2001EGW342 "+4.5V" ? Solder line
1
Pin 22 of ROM µPD23C2001EGW342
"Pulse" ?
Solder line
Yes
No
No
Replace CPU.
1
Poor connection
on ROM or CPU?
Poor connection on ROM, RAM or CPU ?
1
No
Solder line
Replace ROM, RAM or CPU.
Yes
Yes
Yes
No
Poor connection?
No
No
No
No
No
No
No
No
Yes
Yes
1
No
1
No
Yes