TC-P50VT20 10 Blink Code

[tw2005]

Re: TC-P50VT20 10 Blink Code

I figured out that the SU and SD boards are the buffer boards. The test points on my board were different than those shown in the Troubleshooting handbook, but I was able to do the tests from the pinouts and got roughly the readings specified.

The 5V_F reading on the SD board was roughly 10 MOhm Rather than the 5.7, but it was definitely not shorted.

As soon as I hear from you regarding the troubleshooting anomaly above, I'll wrap this up and send this for rebuild.

There's three resistance test points to test. Vfo is a good one to check as it will go short on a bad board in most cases

[tw2005]

Re: TC-P50VT20 10 Blink Code

TW, I hate to bother you again, but I was reading through the Troubleshooting handbook you gave me trying to find the word Buffer (to test the buffer resistance) and I couldn't find it. Is there another word for buffer or a specific page for that procedure.

Also, as I was pouring through that manual, I found it was WAY more useful than the similar manual I have for my specific TV. It actually has a 10 Blink Code troubleshooting procedure. So, just for fun, I decided to run through it just to prove what I think I already know (that the SC Board is bad).

But when I run the procedure on page 53, I get to the point where I disconnect SC20 and power the unit on, and I still get the 10 blink code. according to the procedure, it would appear that my problem is in the A Board based on that. If the SC Board is the culprit, the procedure says the LED should blink 6 times with SC20 Disconnected.

Is this an error in the procedure or is the VT20 different than the G series TVs?

Well for me if you found 6 shorted out IGBTs on the SC board then there's really nothing more to be said about that.

Of course I'm relying on data you have posted but all the ones you say are shorted are generally always shorted when these boards fail.

What you're worried about I presume is , is it really causing 10 blink.

It's definitely known to cause 10 blink, and we know it's bad.

So where are we heading now? Looking for a second board that failed?

Possible I guess, I have had a blown SS board and a faulty A-board in one TV.

I guess I'll have to come up with a way to prove it is not.

If It was the 2D model I have an easy way but this has a d-board so i'll have to think about it.

[tw2005]

Re: TC-P50VT20 10 Blink Code

Step 1:

Is there a short circuit of the Vsus, Vda, or P15V? Follow the procedure on page 8 to check the Vsus, Vda, and P15V for short circuit or low resistance reading.

what resistance values do you get particularly on the P15V and, Vsus (across the SC2 pins).

[tw2005]

Re: TC-P50VT20 10 Blink Code

Try this.

TV off.

disconnect:

SC board
SC2, Sc20,

SS board:
ss11,

P-board:
P35, P65,

D-board:
D31,D32,D33,D34

turn the TV on, I expect the fans will be running if it's on.

Once you've confirmed a result, turn it off and leave it for about 10 mins before you reconnect any of those leads especially P35,P65 or you can arc the panel due to residual voltage.

[Katzat]

Re: TC-P50VT20 10 Blink Code

Step 1:

Is there a short circuit of the Vsus, Vda, or P15V? Follow the procedure on page 8 to check the Vsus, Vda, and P15V for short circuit or low resistance reading.

what resistance values do you get particularly on the P15V and, Vsus (across the SC2 pins).

I did that test as well. All was good according to the manual. All more that 1kOhm.

[Katzat]

Re: TC-P50VT20 10 Blink Code

Well for me if you found 6 shorted out IGBTs on the SC board then there's really nothing more to be said about that.

Of course I'm relying on data you have posted but all the ones you say are shorted are generally always shorted when these boards fail.

What you're worried about I presume is , is it really causing 10 blink.

It's definitely known to cause 10 blink, and we know it's bad.

So where are we heading now? Looking for a second board that failed?

Possible I guess, I have had a blown SS board and a faulty A-board in one TV.

I guess I'll have to come up with a way to prove it is not.

If It was the 2D model I have an easy way but this has a d-board so i'll have to think about it.

Since I know the SC Board is toast in all the normal places, I think I'll just send that one for repair and fix something else if if necessary after that's fixed.

[tw2005]

Re: TC-P50VT20 10 Blink Code

I did that test as well. All was good according to the manual. All more that 1kOhm.

SC2 can read 300k-over 2 megohms so it would be interesting to know the measured value.

A generic value of 1k or over being classified as not shorted or low reading for SC2 is unrealistic.

These guides are not always accurate.

you could try my other suggestion, I'm thinking it should either turn on or go 6 blink.

[Katzat]

Re: TC-P50VT20 10 Blink Code

SC2 can read 300k-over 2 megohms so it would be interesting to know the measured value.

A generic value of 1k or over being classified as not shorted or low reading for SC2 is unrealistic.

These guides are not always accurate.

you could try my other suggestion, I'm thinking it should either turn on or go 6 blink.

P15V = 2.5 kOhm
Vsus = 5.7 MOhm
Vda = 4.2 MOhm

I've since removed the SC, SU, and SD boards in preparation for sending the SC Board for repair. Could the other test still be performed with those out of the set completely to see if I get 6 blinks?

[tw2005]

Re: TC-P50VT20 10 Blink Code

P15V = 2.5 kOhm
Vsus = 5.7 MOhm
Vda = 4.2 MOhm

I've since removed the SC, SU, and SD boards in preparation for sending the SC Board for repair. Could the other test still be performed with those out of the set completely to see if I get 6 blinks?

sure, I am somewhat curious to find out what it does.

interesting results. So 5.7Mohms across SC2 ?

[Katzat]

Re: TC-P50VT20 10 Blink Code

sure, I am somewhat curious to find out what it does.

interesting results. So 5.7Mohms across SC2 ?

Yes. It is decreasing. I guess there's a cap in the circuit that's biasing a transistor gate or something. I didn't wait to see how low it would go, but it's definitely not shorted.

I'll run that test tonight and report back.

[Katzat]

Re: TC-P50VT20 10 Blink Code

sure, I am somewhat curious to find out what it does.

interesting results. So 5.7Mohms across SC2 ?

OK, It took me a couple of evenings, but I ran the test with everything you specified disconnected.

Yes, the fans ran when it was turned on, but it never shut off and I got no SOS code. No 10 blinks and no 6 blinks. It was like it thought it was running just fine.

The SC board has been sent away for repair and I'm now waiting for it to come back for reassembly.

[tw2005]

Re: TC-P50VT20 10 Blink Code

OK, It took me a couple of evenings, but I ran the test with everything you specified disconnected.

Yes, the fans ran when it was turned on, but it never shut off and I got no SOS code. No 10 blinks and no 6 blinks. It was like it thought it was running just fine.

The SC board has been sent away for repair and I'm now waiting for it to come back for reassembly.

That's a good sign. Should be happy days

[matu]

Re: TC-P50VT20 10 Blink Code

Hi, i have a similar problem discussed above but refer to model
TX-P42VT20. Well, continiously this TV gives me 10 blinks error code when switched on. I have changed the main A board for the beginning which didnt give a result. Then I changed the SC board, following with D-board, no big difference still 10 blinks error. All transistors and diods are checked on SC boards for short before installed by my tech.friend also SS boards seems to be working. If I switch tv on with orig. videoboard, on the board the optical red lid is on. I did the test described here(i dont know is it suitable for that model also):
SC2, SS11, P35, and the 3 white ribbons(only one wide white ribbon present) on the side of the A-board.Now turn it on, if it turns on and no error blinks the P and A are ok. Do this for less than 30secs." Still the same!

All boards ordered are matching labels and asked for 42" model.
One weird case if i swap between A-boards, then switching tv on with orig. A board the green lid blinking longer time then turn back to 10 blink error code. Ther is only one board i havent changed - the SS, regards to 10 blink error code. But before to make another investment, i need to be sure. So, would be very grateful for any help how to find the failed one.Thanks

[tw2005]

Re: TC-P50VT20 10 Blink Code

Hi, i have a similar problem discussed above but refer to model
TX-P42VT20. Well, continiously this TV gives me 10 blinks error code when switched on. I have changed the main A board for the beginning which didnt give a result. Then I changed the SC board, following with D-board, no big difference still 10 blinks error. All transistors and diods are checked on SC boards for short before installed by my tech.friend also SS boards seems to be working. If I switch tv on with orig. videoboard, on the board the optical red lid is on. I did the test described here(i dont know is it suitable for that model also):
SC2, SS11, P35, and the 3 white ribbons(only one wide white ribbon present) on the side of the A-board.Now turn it on, if it turns on and no error blinks the P and A are ok. Do this for less than 30secs." Still the same!

All boards ordered are matching labels and asked for 42" model.
One weird case if i swap between A-boards, then switching tv on with orig. A board the green lid blinking longer time then turn back to 10 blink error code. Ther is only one board i havent changed - the SS, regards to 10 blink error code. But before to make another investment, i need to be sure. So, would be very grateful for any help how to find the failed one.Thanks

This being a 3D model makes it a bit different especially the " 3 white Ribbon "bit but if you read above what was done The TV turned on with no error blinks? Did you read the previous posts?

Have the TV off, disconnect SS11, turn it on and post up what happens

[matu]

Re: TC-P50VT20 10 Blink Code

no. there is always only 10 blinks, SS and SC disconnected both or only one at time. Two second green flashes, relay click and 10blink failure code.nothing on the screen.

[tw2005]

Re: TC-P50VT20 10 Blink Code

no. there is always only 10 blinks, SS and SC disconnected both or only one at time. Two second green flashes, relay click and 10blink failure code.nothing on the screen.

Try the instructions in post 24 watch out for residual voltages after each power cycle .

Especially p35 p65 that feed the c boards and panel

[matu]

Re: TC-P50VT20 10 Blink Code

Try the instructions in post 24 watch out for residual voltages after each power cycle .

Especially p35 p65 that feed the c boards and panel

Thats what i did:
TV off.

disconnect:

SC board
SC2, Sc20, - disconnected, same numbers on my SS board

SS board:
ss11, - disconnected from P-board P11, SS11 cant reach

P-board:
P35, P65, - on my board there is P35 and P6( which is connected to A-board),both disconnected. P25 goes to D-board, stay connected.

D-board:
D31,D32,D33,D34 - on D-board there are D31 and D32 (disconnected both).
Others D20 disconnected from SC board, D5 connected with A-board.

And result is - there is no difference in behaviour.

[tw2005]

Re: TC-P50VT20 10 Blink Code

Ok looks like i need to look at a manual. Obviously the 42 is different. No c boards along the top just the bottom by the sounds of it in which case some of those are missing. P6 needs to be connected.

Got 10mins of tv to watch then i can get on my pc.

[matu]

Re: TC-P50VT20 10 Blink Code

yes, only two c boards on the bottom.I can provide photo from the back if needed. Thanks for your efforts

[Katzat]

Re: TC-P50VT20 10 Blink Code

TW, you are doing the Lord's work. Thanks so much.