Hitachi VK-U174 Service Manual page 23

Troubleshooting > Trouble Diagnosis
(3) No power
No
Check fuse
(F3501)
Yes
No
TL3511 : 9V (+B)
Yes
No
TL3005 or TL2501 :
5V
Yes
No
TL3006 or TL4006 :
3V
Yes
No
TL3007 or TL1212 :
2V
Yes
No
TL3008 : 15V
Yes
Yes
TL3009 : -7V
No
D3006 faulty
Fuse replacement
D3007 or C3501 faulty
No
IC3001-44 : 8V IC3001 faulty
Yes
Q4105 faulty
No
IC3001-35 : 8V IC3001 faulty
Yes
Q4106 faulty
No
IC3001-2 : 8V IC3001 faulty
Yes
Q4107 faulty
No
TL3009 : 7V
Yes
D3005 faulty Q3004 faulty
No
TL4023 : 6V IC3002 faulty
Yes
Correct the connections
of circuit boards
Circuit No. Circuit Board
1000 to 1099
1100 to 2999
3000 and higher
No
IC3001-41 : 8V IC3001 faulty
Yes
4 - 4
SP
PC
CSR