Question about Sony CFD-S300 Radio/Cassette/CD Boombox

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No power to unit. All functions dead.

I have used this unit very little and when I turned it on the other day nothing happened. I checked my 120 Volt source and the power cord and I had power to unit. I dismanteled covers to see if there was a fuse but could not find any. The unit had not been used for approx. 4 months prior to turning it on and it had always functioned properly before.
The product is out of warranty and Sony has a program of replacement with a refurbished unit which actually cost more then I can by a new unit for.
I would appreciate any help in troubleshooting the problem.

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  • perry0024 Feb 18, 2009

    Thank-you Jee for your help. I will check it out this weekend. I forgot to mention that it does'nt work on batteries either. Do you think it could still be the power transformer.


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Please check AC transformer in CFD-S300 that seems fried (open)
if it found bad, you can buy it under following part number..
It is available in Part Store.

Posted on Feb 17, 2009

  • Shahid Electronics
    Shahid Electronics Feb 18, 2009

    Now senerio is changed as you mentioned it does not function with batteries.
    Please check does unit has power supply volts input from power supply board.
    Now service manual, schematics would be helpful to find what is wrong with this tape.


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