I already did it brother, follow the fault. I turn it off and it looks good one or two minutes, then the horizontal stripes begin to appear, then vertical and gradually they get stronger, after a while it looks like a window, with a frame around where the effect is less noticeable. Thanks for your reply Antonio
you have a problem with the tcom card because of the characteristics you give me measures the voltages on the tcom card before and after the failure. Also connect a DVD to see how the image behaves so you discard the part of the video selector
It is the same with DVD, it even presents the fault without video signal. I leave it without a signal, it presents the little square that runs along the zul screen saying that there is no signal and the hairline shows up at the end. A`pay and I preder again and you see blue screen for a minute or so.
In the serigraphy I don't have the T-Com voltages marked and I don't have the diagram
and the audio comes out tuning to a channel, the vol voltages in the tcom are usually these negative VGL 6 volts VHG 26 volts, VAAP 18 volts VDD 16 volts these are the four voltages that you have to measure you have to be sure that the Failure is not causing the video card for the symptoms it seems the tcom has this test disconnect the connector of the tcom card with the video card and test what symptom gives you
The audio is heard perfectly. I did the test he told me by disconnecting the cable between the Video Card and the T-Com. The screen is illuminated and a clearer trace is seen in the upper part with a window effect, then the horizontal lines of colors began to appear in that area and then disappeared and the screen remained uniform only with the backlight. Tomorrow, God willing, I measure the voltages in the T'Com.
evidently the tcom measures the voltages to see that light that is seen are the lamps that are illuminating
Good evening at the T-Com I measured the following voltages; Von 27v, AVDD 14.5, Vcc 3.3, Vss -7, Vrefu-h 14.5, Vrefu-l 8.5, Vrefl-h 6.04 Vrefl-l 143 mvolt. Apparently the single voltage that does not appear is marked as VREFL-L that measures only 143 mv. The voltage measurements are the same before and after the fault occurs. Good night
the integral circuits that have the tcom get very hot, look at that detail that voltage you need is important for the tcom to work correctly
Good afternoon Antonio, no integrated circuit is heated in the T-Com. Check the LVDS signals with an oscilloscope and find that there is no signal in par four and that in par three shows a slight distortion. I think the problem is in the Main Card. The integrated one where the LVDS signals are generated is very hot
You have no chance of getting a main card borrowed with someone to get out of doubt I imagine you mean the micro processor place a fan to see if at least you see the image
that integrated is commercial if you have the possibility of changing it must be very expensive
The image looks good at the beginning, then vertical and horizontal lines begin to appear that obscure the image. Can this effect be caused by the lack of one or two LVDS signals?
The lack of the LVDS signal could be due to false contact in the integrated? What do you think about applying heat to the integrated?
Tomás, I live in Venezuela, I also consult with colleagues in this country by free market, they offer everything is to see prices
If there are technicians who resort to this technique of applying heat to the integrated and solve the fault, the important thing is to test it for several days before delivering it to the customer.
put a fancooler to the microprinter to see the behavior of the fault the other thing is to apply the reballing to the microprocessor if you have false contacts in it
I am looking for the free market card is the T.MT8223.3B. Check and there is no false contact. The LVDS signal in par 4 is absent, measuring at the output of the integrated climber. Signals 3 and 5 are altered.
Today I did the test again disconnecting the signals from the T-CON, leaving only the power supply. I measured the voltages with the same result and the screen looks normal, with its backlight activated and semi dark
It is not easy to get that card and I asked colleagues to see if they have it and nothing and searched for free market and I have not seen that once you look for a card from another TV in free market I saw that in calling for a repair service All types of cards with a six month warranty ask since you are in Margarita Island
You have not tried to heat the micro by doing a reflow to see if it is by false contact I told a colleague the fault and he told me that if the signals do not arrive lvds the problem is in the micro
doing the reflow can be the solution you have to be careful with the time and temperature for the reflow on the internet there are several tutorials that guide you
The Main Card is T.MT8223.3B 10285, the micro is surface mounted, it is not BGA technology. I will take your advice to make the Reflow very carefully. I'll tell you later, now I'm out of town
The image begins well, as the minute the color lines begin to appear and then the image becomes whitish, very diffuse with horizontal and vertical white lines. Turn off and on and the image is shown again and the fault is repeated
The image looks good when you turn on the TV, as after 2 minutes the colored lines begin to appear in stripes, then the image turns white. I turn off and on and it goes back to observing well and the phenomenon is repeated. The image turns white,
You took the reflow to see if there is improvement in the image You take a look at the strips that go from the tcom to the screen these tend to fail a lot due to welds click to see
you take when the image is well measured the signal lvds and when the fault appears the ace measured to compare before the fault and after the fault
In the strips I still have to check the part that connects to the screen. I do that and I tell you. I will also place the oscilloscope fixed on par 4 LVDS to see if there are variations before and after the fault. I have really seen the signs after the fault
Good morning Antonio, I applied heat, I cleaned the strips and the LVDS signal in par 4 still does not appear. When turning on, the presence of DC voltage is noticed, as in the other lines, but the LVDS signal does not appear in that pair. I'm still searching for the Main Card. Disconnecting the TCON, the signal does not appear in par 4. I returned the TV to the Client waiting for a Main to appear.
Thank you very much for your interest in the case.