Oki B4100 - Manual (Page 259)

40055101TH Rev.4 259 /
(4) No 24 V output
Yes
Yes
Yes
No
No
No
Replacement
Replacement
Replacement
1. Q1 short circuit
2. Q3 short circuit
3. R9 open circuit
4. D8, D9 or D10 short circuit
1. ZD7 or ZD8 short circuit
2. C22 short circuit
3. ZD5 short circuit
4. Check any short circuit on the load side.
5. D9 open circuit
1. Q4 open circuit
2. R24 open circuit
3. ZD3 or ZD4 open circuit
Is there oscillation
waveform at VCE of Q1?
Is the voltage across
C22 at 24 V or more?
Is the voltage across
C23 at 24 V or more?
End
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