Hitachi VK-S274R Service Manual page 18

Troubleshooting > Trouble Diagnosis
(3) No power
NG
Check fuse
(F1501)
OK
NG
TL1609 : 9V (+B)
OK
NG
TL1535 : 9V (+B)
OK
NG
TL1539 : 5V
OK
NG
TL1540 : 3V
OK
NG
TL1532 : 2V
OK
NG
TL1533 : 15V
OK
OK
TL1534 : -7.5V
NG
D1503 faulty
The test lands and components of circuit no. 1000-1099 are
on the SP circuit board.
The test lands and components of circuit no. 1100-1499 are
on the PC circuit board.
The test lands and components of circuit no. 1500 and higher
are on the CSR circuit board.
Fuse replacement
D1601 faulty
CP1601 faulty
NG
IC1501-44 : 8V IC1501 faulty
OK
Q1501 faulty
NG
IC1501-35 : 8V IC1501 faulty
OK
Q1502 faulty
NG
IC1501-2 : 8V IC1501 faulty
OK
Q1503 faulty
NG
TL1534 : -7.5V
OK
D1501 faulty Q1504 faulty
NG
TL1522 : 7.2V IC1502 faulty
OK
Correct the connections
of circuit boards
NG
IC1501-41 : 8V IC1501 faulty
OK
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