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ELECTRICAL TROUBLESHOOTING GUIDE
1. Power Circuit(SMPS)
(1) No 5.3VA.
No 5.3VA.
YES
NO Replace the F101
Is the F101 normal?
(Use the same Fuse).
YES
NO
Is the BD101 normal? Replace the BD101.
YES
NO
Is the R101 normal? Replace the R101.
YES
Does the oscillation waveform appear at NO Is Vcc(about 13~15V) permittable at the
the IC101 Pin 1? IC101 Pin 4?
YES NO
Check or Replace the D103.
NO
Is there DC voltage at the IC101 Pin 5? Replace the IC102.
YES
NO
Is there about 2.5V at the IC103 Vref ? Replace the IC103.
YES
NO
Is the D106 normal? Replace the D106.
YES
Check the Main PCB 5.3VA Line short?
3-3
7. Power Circuit(SMPS)
(2) No 12VA.(Capstan)
No 12VA.
YES
NO
Does 5.3VA work normally? Check whether 5.3VA is out of order.
YES
NO
Is the D109 normal? Replace the D109.
YES
Check 12VA Line of the Main PCB short.
(3) No 12VA (Hi-Fi, Buffer)
No 12VA.
YES
NO
Is Vcc(about 14VA) put into the Q155(+)? Replace the Peripheral Circuitry of Q155.
YES
Is Voltage(about 14V)
put into the Q155(-)?
YES
Check or Replace the Q155.
3-4
7. Power Circuit(SMPS)
(4) No 5VT(5V)
No 5VT.(5V)
YES
Is 5.3VA put into the Q152(Q151)
collector?
YES
NO
Is the Q163(Q162) Base "H"? Check the