Sharp Aquos LC-40F22E - Not switching on!

[Rhothgar]

Hi

Been scratching my head on this for a couple of weeks now.

Neighbour was throwing TV out and I said I'd have a look at it. He says I can have it if I can get it working.

He tried changing capacitors on power board and ended up buying a replacement power board. No joy!

So the symptoms are that there is NO Standby LED when the unit is powered. The control board beeps when the buttons are pressed. I've tried a service reset but couldn't find exact reset technique for this TV anywhere.

If I unplug the inverter board, the standby LED comes on and flashes 5 times twice. (This is course might be telling me that there is an inverter fault...)

I noticed one of the dual channel transistors had blown so replaced that and still on joy. There are some burn marks to the underside of the inverter.

From memory, it was a few days ago, I think I was getting intermittent voltage to the inverter on connector PL802.

[Rhothgar]

Re: Sharp Aquos LC-40F22E - Not switching on!

[R_J]

Re: Sharp Aquos LC-40F22E - Not switching on!

Check the transformer secondaries and compare them, I suspect one is going to be bad, likely the one that had the shorted fet.

[Rhothgar]

Re: Sharp Aquos LC-40F22E - Not switching on!

The ones on the inverter or the power board? The power board does seem intermittent?

I never found a wiring diagram for the inverter board during my searches for information.

How would I go about testing the transformers on the inverter please? Other issue is it states 1000V on the inverter and my DMM only goes to 600V. Any chance you could do a markup for me on the photo to show what goes where on the transformer input and output please?