Your hitachi tv problem....

My Hitachi used to eat Horizontal output transitors. I do not even know if your uinit has that anymore, but if that goes out the unit wont make the B+ voltage needed to power up the unit.

Can you try and see if it is your source that has the lines or the actuall TV that has the horizontal lines.
What is your source? Direct TV, Cable TV or even off air Digital TV.
If you remove your source do you still get the horizontal lines? If you do then what colors are they? Seems if when you remove your source input and you still have these H-lines then you have issues with your individual LCD palets. Especially if they are just Green, Red or Blue?

I have had the same problem with the same TV .You need the Hitachi cable that runs from TV to control box.No other able will work,Whenyu have his it will autmaticaly change over for you.

Need the model number of the Hitachi which should be listed n the rear cover. I should be able to assist but will need the Model Number to determine which chassis design you have.

Since you have a picture for 10 to 25 min., we know that nothing is directly shorted. Look for bad connections in power supply and horizontal circuit or possibly bad capacitors in power supply.

most likely you have cold solder joints on t401 the horizontal drive tranformer. Also check that little blue capacitor in front of the horizontal output transistor.

Sounds like a bad component on the video board. These days, TV techs just swap out boards for whole new ones.

Did you check the resitors out of circuit? As its very rare when a Hitachi doesnt open at least two on the affected circuit. If you checked the resistors in circuit an open resitor will read good even though its actually open.

this is a job for experienced tech maybe your horizontal circuit is bad there is a blue capacitor that is comom go bat and short horiz. out transistor

You have a defective light engine. We just went through this and we have the same TV that you have. Hitachi knows about the problem but will play dumb when you first call. If you deal directly with their Customer Relations Department 800-654-7013, it will make a lot of difference than regular customer service.

Here's how they handled our situation. We called Hitachi after lots of research online and they gave us the names of some certified dealers in our area. The tech came out and in less than 1 minute said the TV had a defective light engine. We called Hitachi back and low and behold, they are aware of the problem...imagine that. Hitachi called the dealer directly and once the dealer confirmed the problem, they agreed to send a brand new light engine out to the dealer and the tech came out and replaced it. Here's the kicker...Hitachi will pay the for the part ($1500) but they ask you to pay for the install. Our install was $400. This was worth it to us being that we spent $3600 on this set 3 years ago. Once the light engine was replaced, the TV looked BRAND NEW! Please deal with their customer relations department at the number I lised above. If you deal with customer service, they will have you chasing your tail...so to speak! Good Luck! If you're willing to cover the install, the rest should go pretty smoothly..at least it did for us:)