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I have an Hitachi 56 inch Projection tv model#57F500A. The other day I turned it on and the power indicator on the front came on but no picture. I also noticed that I can turn it on with the remote but it will not turn it back off. I looked at the power board and one of the green led's did not light up. I read a forum that mentioned this same problem and the person changed a 3000ma pico fuse,E907,that fixed the problem. I checked E907 and it is open. My question is, if I replace the pico fuse will this fix my problem or do I possibly have a problem with a chip.
 

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E907 is on the 115V B+ line and has nothing to do with the common convergence ICs. I would look for a shorted output transistor or shorted capacitor.
 

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Sorry to seem so dumb, but could you possibly suggest transistor and capacitor component numbers as they appear on the board?
 

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I do not recall exactly by model number, but C707 is a common high voltage cap that shorts. The output transistor is likely also numbered in the 700s.
 

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I finally got around to checking C707 and it is open. Can you tell me how to determine what the value of the capacitor is. It is labeled B - 222K - KCK. I went to a local electronics shop and the man said I would need a service manual to determine the value of the capacitor. He also said that he did not know what a pico fuse was and that he did'nt think it was a fuse because it had an orange band on one end. He said that indicated polarity, which is usually associated with a diode. Just wanted to make sure I'm looking at the right components.
 

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Hitachi part number: 0244505R
CAP-CERAMIC 0.0022UF-K 500V

Did you check its capacitance? A capacitor is OPEN when measuring its ohm

You need a service manual of 51UWX20B for you model.
 

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This is correct for capacitor. It should read infinity.

For capacitor you need to check capacitance with digital multimeter
 

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This is not the value of the cap that I recall having a problem with in Hitachis. It is a 1000 or 820pF cap with a voltage rating of 2kV. It may be numbered differently in this model or may not be a common issue with this one.

Regardless, the set will require skilled troubleshooting. This may require equioment beyond a DMM.
 

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agreed, :yes: I think this kind of power issue is something easy for a trained tech.

Capacitors may measure ok but behave bad when voltage applied. It happened to me once with a high voltage ceramic cap which gave me intermittent issue.
 
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