Olevia 265-t12 - no place to turn but the Internet

[PlainBill]

Re: Olevia 265-t12 - no place to turn but the Internet

OK so I tested the power connectors connecting to the inverter boards. There are some inconsistencies but I dont know if it means anything. I will label the inverters for this purpose 1-6 going from the bottom left clockwise through the bottom right. All red wires measure the same for the respective inverters.

Inverter 1 - 54.7
Inverter 2 - 54.7
Inverter 3 - 54.7
Inverter 4 - 53.9
Inverter 5 - 53.9
Inverter 6 - 53.8

I set the DMM to the setting of 200 on the dial where there is a V~. The power stayed through the 2 seconds to black so the inverter appears to be the one that triggers the fault.

I tried to measure the actual voltage output to the bulbs but I couldnt find the right setting to measure as when the power turned on the reading went to 1. then black back to 0.

Hope some of this makes sense to any of you. Please help me to the next step

You really don't want to measure the inverter output voltage. You are looking at something over 1000 volts at 40 Khz. Most DMMs can't handle the voltage or the frequency.

PlainBill

[chcbearsfan]

Re: Olevia 265-t12 - no place to turn but the Internet

V~ is AC. We want to measure DC.

Thanks for that. I remeasured and got consistentcy from each Inverter set.

Inverter 1 - 25.1
Inverter 2 - 25.1
Inverter 3 - 25.1
Inverter 4 - 24.7
Inverter 5 - 24.7
Inverter 6 - 24.7

That should be the DC readings for power to the inverter boards. does that mean anything?

[retiredcaps]

Re: Olevia 265-t12 - no place to turn but the Internet

I remeasured and got consistentcy from each Inverter set.

Inverter 1 - 25.1
Inverter 2 - 25.1
Inverter 3 - 25.1

The legend says 24V DC. 25.1 is a tad high, but your multimeter may not be very accurate since it is on the 200V DC scale. Under load, it might actually be closer to 24V DC as well.

For now, I would assume this is okay. If one read 13V DC, then I would say we have "smoking gun".

[tom66]

Re: Olevia 265-t12 - no place to turn but the Internet

The next step will be to get a part number for the inverter boards and try and find the pin-out of the connector going to the master. It's possible the main board is shutting down the inverters itself.

[chcbearsfan]

Re: Olevia 265-t12 - no place to turn but the Internet

The next step will be to get a part number for the inverter boards and try and find the pin-out of the connector going to the master. It's possible the main board is shutting down the inverters itself.

Hi Tom I am not sure how to do that but I can get the part numbers. There are 4 different inverter boards. I will label each below the same way. Starting from the bottom left through clockwise.

Inverter 1 - RDENC2244TPZZ IM3818-2
Inverter 2 - RDENC2243TPZZ IM3818-1 (master - already replaced)
Inverter 3 - RDENC2244TPZZ IM3818-2
Inverter 4 - RDENC2246TPZZ IM3818-4
Inverter 5 - RDENC2245TPZZ IM3818-3 (slave)
Inverter 6 - RDENC2246TPZZ IM3818-4

So what next?

[Mad_Professor]

Re: Olevia 265-t12 - no place to turn but the Internet

Why does this TV have two power supplies?

If anything I would look at the Power-supplies as the problem if one has failed and not providing power to one of the 6 inverters, that would be enough to bring the set down.

[chcbearsfan]

Re: Olevia 265-t12 - no place to turn but the Internet

Why does this TV have two power supplies?

If anything I would look at the Power-supplies as the problem if one has failed and not providing power to one of the 6 inverters, that would be enough to bring the set down.

A few posts back I noted the output voltages for each red wire on each inverter. They were all consistent and within an acceptable range per retiredcaps.

I am at a loss at this point but it would appear the issue is inverter side? Any and all suggestions welcome. I have invested so much time in this I would hate to not be able to end up with a fix

[chcbearsfan]

Re: Olevia 265-t12 - no place to turn but the Internet

I disconnected each inverter from the tube and attempted to power it on. I connected one tube and then one inverter (6 connections) and still get the 2 seconds to black. For what its worth i guess :/

[PlainBill]

Re: Olevia 265-t12 - no place to turn but the Internet

I disconnected each inverter from the tube and attempted to power it on. I connected one tube and then one inverter (6 connections) and still get the 2 seconds to black. For what its worth i guess :/

That's normal. the inverter contains protection circuitry which typically monitors the voltage across and the current through each CCFL. If either is out of spec, the inverter shuts down.

PlainBill

[alexanna]

Re: Olevia 265-t12 - no place to turn but the Internet

This looks to be a really strange setup.
Is there any connection between the two power supplies,other than the AC source?
On the inverters do they all have there own controller for the inverter?
Where the inverters come together,is there a connection between them?

[tom66]

Re: Olevia 265-t12 - no place to turn but the Internet

Could you post a clear and detailed shot of the connector which connects to one of the inverters in this image with the white wires?

Does that connector go the main board? If so, post a picture on the main board side, too.

Also, try removing the inverter with this connector and posting a picture of the bottom - if you're lucky, there will be a key to the pins on the bottom.

[chcbearsfan]

Re: Olevia 265-t12 - no place to turn but the Internet

This looks to be a really strange setup.
Is there any connection between the two power supplies,other than the AC source?
On the inverters do they all have there own controller for the inverter?
Where the inverters come together,is there a connection between them?

From the Power supplies there are 3 power outputs to the each inverter per board, totalling 6. Then there is a red/black connection, which is assume is the AC source and there is a couple of connections to the AV input section.

The inverters appear to be controlled by the middle inverter in the series where the ccfl outputs are blue/white wire combination. I am posting a pic of one I replaced and is dismounted from the TV.

The big white wire clump is where the master and slave inverters are connected. I took several pictures, hoping one of them gives a clear shot to the markings and is what we are looking for. Let me know

[chcbearsfan]

Re: Olevia 265-t12 - no place to turn but the Internet

Could you post a clear and detailed shot of the connector which connects to one of the inverters in this image with the white wires?

Does that connector go the main board? If so, post a picture on the main board side, too.

Also, try removing the inverter with this connector and posting a picture of the bottom - if you're lucky, there will be a key to the pins on the bottom.

The big clump of white wires is what connects the slave and master inverters together. The small bunch of white wires on the pics i just posted are what look to connect to a control board of sorts. I took oa picture of the back and also another where you can see the wires go underneath the AV in/out section and under the control headed to the other inverter board.

I copied a pic offline of what the exposed control board looks like. I would have to remove the power supply and the metal covering to get to it on my panel. Hope that helps.

[PlainBill]

Re: Olevia 265-t12 - no place to turn but the Internet

I've tagged a number of semiconductors in the attached picture.

1 thru 6 are 16 pin ICs. What are the part numbers (I suspect they may be identical)?

7 appears to be a power transistor or voltage regulator. What is it's part number?

8 is the one I am most interested in. It is most likely the inverter controller. What is it's part number?

PlainBill

[chcbearsfan]

Re: Olevia 265-t12 - no place to turn but the Internet

OK, So I finally got back around to this project. I found the problem. One of the tubes is half dark. So there are a bunch of tubes and one is dark on the right side of the LCD panel. I know which one!

Now what do I do? Could it be that bulb since half of it appears to light up? I can post some pics later for reference.

Thanks for the assistance and patience everyone

[kc8adu]

Re: Olevia 265-t12 - no place to turn but the Internet

either the lamp is bad or that channel of the inverter is bad.see lots of bad tranformers on these.since you have extras now swap that transformer with one from your spare boards

[chcbearsfan]

Re: Olevia 265-t12 - no place to turn but the Internet

either the lamp is bad or that channel of the inverter is bad.see lots of bad tranformers on these.since you have extras now swap that transformer with one from your spare boards

I had already swapped the entire inverter and the problem persisted. The confusing thing for me is that the CCFL looks like on long horizontal tube and my mind tells me that if it were the tube the whole thing would be dark. But I dont know how it actually works.

I am pretty sure its not the transformer or the inverter board and I measured all output, fuses, etc. So it means the tube right?

If it is, where do you find one?

[chcbearsfan]

Re: Olevia 265-t12 - no place to turn but the Internet

As a follow up I was able to determine the panel info. It is a Sharp LK645D3LZ29. I measured the length of the CCFL bubs and without pulling it and getting it exact its about 58 inches long.

Hope that helps

[zodono]

Re: Olevia 265-t12 - no place to turn but the Internet

is this solved? mine is doing the exact same thing: (

[chcbearsfan]

Re: Olevia 265-t12 - no place to turn but the Internet

Hi zodono, sorry for the late response but yes I resolved the issue but have another problem. What I did was take the panel down to the tubes and when powering on I could see one of the CCFL was only illuminated halfway. This led me to isolate the transformer on the board that was faulty. I purchased a replacement board so I pulled a transformer from that and soldered onto the inverter in its place and it had been working well for up until recently.

The problem resurfaced and I did the same thing and found a new transformer is having a problem. So I proceeded with the same fix and in the process damaged a couple pads from the transformer. So I bought the same inverter board from ebay and now it just powers down after 2 seconds. So I think there is a fault with this one. I am exhausted with dealing with the set.

I think I am going to give up on this set and get what I can get from another adventurous home electrician.