Hitachi 42HXT12U Inverter Failure

meic2

HI All.

I have a Hitachi 42HXT12U with what I strongly suspect is a failed inverter. On power up the Hitachi splash screen appears for a split second and then disappears. I do have audio but no visual however when shining a torch across the screen I can see the images which leads me to believe it is the inverter and not the back light that has gone.

I've removed the cover and the metal foot plate, I just need someone to confirm that the part in the red square on the attached picture is the inverter and the two strips it is attached to are the LCD strips.

Many thanks

noiseboy72

I think that's the LCD driver board rather than the inverter. Is there a heavier connection directly from the power supply board?

meic2

I think you may be right. This is the part circled apparently is a T-Con (I don't actually know what this is/does) which I have found on a spares website. There are two cables leading from the power distribution board, one goes directly to the input board on the right and the other short cable at the top of the board disappearing under some black tape and into the main structure of the TV which you can see on the picture (sorry its poor quality).

Link to T-Con = Hitachi 42HXT12U - T-Con - 6871L-3177G - 6870C-0452A - LC500DUE-SFR1_Control_Merge - £24.00 : Spares2Repair, LED TV Parts, LCD TV Parts, Plasma TV Parts

JayCee

The board on the LHS is a combined psu/invertor.
The "Backlight" is a strip of LED's mounted behind the screen and these are fed from the invertor and thus illuminates the screen.
So, no illumination can either be a complete or partial failure of the LED strips or a faulty invertor...finding out which has failed requires test equipment and the knowledge of how to use it.
You could take a chance and buy/fit a new psu/invertor board.

meic2

Right so that's what ill be replacing then.

thanks for your help

Al Budri

Hi .. This morning (3rd Jan 2017), I had exactly the same issue as yours with my Hitachi
42HXT12U LED Tele (was working fine last night), had it for just about 2 years.  When switch on it flashes the Hitachi logo very clearly but very quickly disappears and I end up with sound only (and very very very faint shadows if you really concentrate on the tele).  I was wondering how you got on with your efforts?  did you order your part?  ..

here is a good youtube vid showing the general bits and explains briefly what these bits do .. I think most LED TVs have the same setup ..                                 
Tell the truth I got a bit lost with the above communication and now not sure which part you were trying?  I could help by trying a part which you havent done already

Happy new year

Al

meic2

Hi Al.

Not fixed yet, it appears the part is only available from small(er) firms which were closed over Christmas and new year so I'm still on the hunt for one.

This is the part you need Hitachi 42HXT12U - PSU - 23145828 - 17IPS20 - 060913R6 - £21.60 : Spares2Repair, LED TV Parts, LCD TV Parts, Plasma TV Parts

To make sure you get the right board you'll need to provide the number off the bar code on the board when enquiring.

I'll let you know if I find one, the company in the link above won't have any in stock for weeks unfortunately.

CrisR

Hi,I've got the exact same problem with my hitachi. About a month out of its 2 year cover! Did either of you manage to fix yours? The part you linked to above is now available but would like to know if it solvef the problem.  Determined not to buy yet another tv until i have tried fixing this one. So frustrating.

CrisR

Fixed it! Took the back of and tested basics first. Power connetion was unstable so used tape to secure it. Then we saw a red wire sticking out from the cpu board, next to another red wire attatched to its solder. Ee went for it and secured it with tape, assuming it had become detatched. Bingo. Omg, what a fantastic feeling when youre on the verge of chucking it in the shed with the other dead tv but decide to have one last look at it. So relieved and pleased with ourselves....50 yr old hijaby housewife and 12 yr old son helper.

marydsmyth

I had same problem following a storm which temporarily reduced voltage (dimmed lights) to house. Sound ok, no vision. After reading this blog, I replaced the main left hand board which apparently includes the inverter. Success! If I can do it (66 year old retired nurse) you can too. Got the board from Spares2Repair online. Cost less than £30 including speedy delivery to NI.