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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 5?

                         YES                                              NO

                                                          Check or Replace the D103.




                                              NO
    Is there DC voltage at the IC101 Pin 4?                    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 (CANAL, Buffer)



                   No 12VA.


                         YES

      Is Vcc(about 14VA) put into the Q155    NO
                                                     Replace the Peripheral Circuitry of Q155.
      Collector?

                         YES

    Is Voltage(about 14V) put into the Q155   NO     1. Check the ZD151 and the Peripheral
    Base?                                               Circuitry.
                                                     2. Check the R105.
                         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 

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