Specifications

— 16 —
N
Replace PCB
< No key input >
N
Replace CPU (LSI1)
Y
Y
Is 13-Pin of CPU (LSI1) sending
the signal?
Y
N
Replace DET1
N
Replace CPU (LSI1)
Y
N
Resolder RAM (LSI3) or ROM (LSI4)
Replace RAM (LSI3) or ROM (LSI4) or CPU (LSI1)
Does key make positive contact with PCB
Ass’y
N
Y
Resolder CPU (LSI1)
Is 1-Pin of S-80752AN (DET 1) 5[V]?
Is 11-Pin of CPU (LSI 1) sending the
signal?
1
Does RAM or ROM (for LX-546AQ)
make positive contact with PCB?
Does CPU make positive contact with PCB?
Y
Replace CPU (LSI1)