Toshiba Regza 47ZV65OU black screen with sound

[npence]

Ok - I have read up on this for hours and not to repeat what has already been said but I would like to be sure before buying inverter(s).

I have checked both Master inverter and Slave inverter inputs from power supply and leads that are marked as 24v have 24v.


When TV turned on, sometimes constant green LED and sometimes constant flashing orange on front of TV; Toshiba logo within frame does light up. According to manual flashing orange means "Abnormal operation of back light. Turn OFF the TV and unplug the power cord. Plug the power cord in again and turn ON the TV." Putting a flashlight on the screen does allow you to make out picture and menu. I did a reset via the menu (while using flashlight). When applying an open circuit (1 probe from voltmeter) to one of the leads going from the slave inverter going to back of set, when no video input, I am able to see part of the TV Setup Menu (about 15% brightness upper left side of tv), this "trick" does not work when sending in video.

Now I have read some posts about checking the fuse on the inverter; I don't see any fuse on either Master or Slave inverter. I see some posts saying issue could be caused by video controller though unsure if that is hearsay.

So I guess my question is do you think this is an issue with Master or Slave inverter and if so how do you tell which one? Other issue? I am not an Electrical Engineer but I did stay at a Holiday Inn Express the other night.

Any and all guidance is greatly appreciated. Oh, one another thing that might make a difference though unsure, the TV died during the process of being moved from the retail store and residence. I do not know if the TV was laid flat or not during the move. All pictures are of Slave Inverter. I can certainly post pics of other boards if requested.

[budm]

Re: Toshiba Regza 47ZV65OU black screen with sound

You can see F201 in the picture of the inverter board.

[npence]

Re: Toshiba Regza 47ZV65OU black screen with sound

Thank you. I am measuring 24v on each side of the fuse (both slave and master inverter) and I believe 120v each side of fuse on controller

[budm]

Re: Toshiba Regza 47ZV65OU black screen with sound

You are getting the 24VDC from the power supply OK, you need to look at the BL_ON (backlights ON) pin to see if it has 3~5VDC on that pin.
I do not know if your inverter board has labels on them to tell you what pin is what or not.

[npence]

Re: Toshiba Regza 47ZV65OU black screen with sound

I am looking to for anything "BL_ON" or similar. Is that pin on both the Slave and Master Inverter?

[npence]

Re: Toshiba Regza 47ZV65OU black screen with sound

Would you be referring to pin 11 noted here on slave?

[budm]

Re: Toshiba Regza 47ZV65OU black screen with sound

Yes, there should be one on the master also.

[npence]

Re: Toshiba Regza 47ZV65OU black screen with sound

3.3v on Master and 3.3v on Slave

[budm]

Re: Toshiba Regza 47ZV65OU black screen with sound

So the ON signal is OK. That means more in-depth troubleshooting needed. It can be the PWM IC is bad.
You did not see the backlights flash on at all? I hope that the lamps are not broken during transit.

[npence]

Re: Toshiba Regza 47ZV65OU black screen with sound

I had to look that one up. The Pulse Width Modulation Integrated Circuit consists of the 2 rectangular chips on each inverter? Is there any way to trouble shoot with a multimeter or narrow down to a circuit board?

[budm]

Re: Toshiba Regza 47ZV65OU black screen with sound

Yes, those two are the PWM IC, have to get the spec sheet first and then check each pin to ground to see if any one of them has shorted to Ground. The spec sheet may also give the application notes on how they are common.y connected to form the circuits.

[npence]

Re: Toshiba Regza 47ZV65OU black screen with sound

Recall, the TV essentially died while it was being moved or on power up immediately after being moved.

Chips on inverters are:

BD9897FS
933 k65

I found the attached at the following though I am a little confused on what I need to be checking. Am I just checking that I have ground on pins 1 and 11?

http://www.alldatasheet.com/datashee.../BD9897FS.html

[budm]

Re: Toshiba Regza 47ZV65OU black screen with sound

Simple test is to find out if any other pin beside the ground pin are shorted to ground, as I indicated on post9, hope the lamps are not broken during transit. The inverter boards have the 24VDC and the BL_ON signal, so all the required signals are all there.
I still do not get the answer if the lamps even flash on for a second or not.
You can take a chance by replacing both inverter boards, but if the lamps are damaged, then that will be another big job.

[budm]

Re: Toshiba Regza 47ZV65OU black screen with sound

Another test to be done is testing the transformer windings, Do you have the P/N as printed on the transformers?

[multimeter]

Re: Toshiba Regza 47ZV65OU black screen with sound

also,if you have a spare ccfl you can take out each connector from the inverter and plug in your spare ccfl if you have one,one at a time,to at least check to see if your ccfls are good.

regzas normally have a metal shielding covering there inverters,the quality in the toshibas is really good,apart from the inverters ,which are "bought" in ,they have darfon inverter transformers ,these have a high failiure rate.

[multimeter]

Re: Toshiba Regza 47ZV65OU black screen with sound

actually those dont look like darfon's,whats the part # ?

[npence]

Re: Toshiba Regza 47ZV65OU black screen with sound

I had to put the project aside for a moment. I will check PWMs tonight.

I do not have a spare ccfl.

Lamps do not flash, not even for a second and I viewed both front and back of TV with cover off when powering on. I was checking some voltages earlier and for whatever reason 1 lamp came on at least partially when tv has no signal input and an open circuit applied; I attached a picture and circled the pin that gives me a partial lamp when open circuit applied.

There were metal shieldings over the inverters; shieldings have been temporarily removed. Part numbers "Peopleworks PPS-CS47NS-S and PPS-CS47NS-M". Slave part# in picture as well.

I am leaning towards what you said earlier in that lamps may have been broken during transit or perhaps a weak weld came loose.

Regarding Transformers, you are referring to Power Supply - correct?

[RJARRRPCGP]

Re: Toshiba Regza 47ZV65OU black screen with sound

According to manual flashing orange means "Abnormal operation of back light. Turn OFF the TV and unplug the power cord. Plug the power cord in again and turn ON the TV."

I'm afraid you need to do that when there's a poco glitch.

Did your power go out and come back on rapidly?

IIRC, my Antec True 430 1.0 sometimes fails to turn the PC on after the power going out then coming back on rapidly until I unplug the PSU and plug it back in again.

[budm]

Re: Toshiba Regza 47ZV65OU black screen with sound

I refer to the Inverter transformers. I do not see hwat else could have gone wrong during the move since I am sure that you have already check to make sure al the connectors are secured. Lamps and the LCD panel are the only two things that are really fragile.