I had the same problem with my Handycam ccd-fx630. I don't know if this applies to your model but After searching for hours I found NO help not even from sony. So I removed all of the small body screws from the tape side of the camera (there is one behind the mic) Slowly work the casing off and on the bottom right of the tape loading carriage there was a 4 prong plug that had come disconnected. Pluged it in and it works fine although it seems to be a poor design and is sure to come undone again unless secured somehow. Also look for small ribbon plug on the bottom center of the carriage as mine was about about to fall out also. It may sound scary busting into your cam but It was very easy and took all of 5 minutes.

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