I'm not sure how to help you with this one as the unit you describe does not match the one listed in the thread. You talk about a WTV1903 TV but a Sony KV-27S42 is listed. One thing is for sure no matter which model you have you should never exceed the manufacturers rating for the fuse (which is not meantioned). You stated that a 4 amp fuse (12V) blew so you put in a 5 amp. You never raise the fuse rating. Larger means more current draw and the possibility of a fire. First put the correct size fuse in. It should be listed on the circuit board or in your literature. If the picture is dark either the CRT is bad or the High Voltage or screen drive is low or both. The fact that it is blowing fuses indicates that something is not working properly. You need to check the CRT with a tester. If good, check the High Voltage for the correct value. If this is good you could have a partially shorted flyback. If you are not qualified to work on these circuits, (they are dangerous) have a qualified tech do it. Good luck and don't put larger fuses in in the future!
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