Vestel 17MB82S Only backlight

[Andreasbest]

Hello.
I got a 17MB82S that give me only backlight, no picture and no sound (not sure about sound as i cannot see if the screen is in HDMI,TV,Scart or USB) no OSD at all too.

[dskall]

Re: Vestel 17MB82S Only backlight

Have voltage to t-con?

[Andreasbest]

Re: Vestel 17MB82S Only backlight

Hello.
Really sorry for the delay, i forgot the whole tv and today i remember it!
Yes i have voltages like 3.3v and 1v. I can write you all voltages at all pins if you want.
Thank you very much!

[Andrew F. Ali]

Re: Vestel 17MB82S Only backlight

Voltage to T-CON means to ask if you have 12Vdc supply voltage to the T-CON Bd. Look at the T-CON Bd. at the bottom of the TV near to where the FFC from the Main Bd. enter the T-CON Bd. There should be a fuse to measure that you have voltage on both sides.

[Andreasbest]

Re: Vestel 17MB82S Only backlight

Yes fuse has voltage (12v) on both pins.

[Dannyx]

Re: Vestel 17MB82S Only backlight

Having the exact same issue....any ideas ? Will try reflashing the firmware via USB just for the heck of it...not like anything can go worse than it already is...

[tom66]

Re: Vestel 17MB82S Only backlight

If you have USB to RS232 cable you can check the UART debug output on the SCART port, some of the pins are connected to the TV's Linux kernel debug UART.

[Andreasbest]

Re: Vestel 17MB82S Only backlight

So the problem is clearly in mainboard?

[tom66]

Re: Vestel 17MB82S Only backlight

No, there's a chance the panel could be bad as well.

[Dannyx]

Re: Vestel 17MB82S Only backlight

+1 - most likely faulty panel

[Andreasbest]

Re: Vestel 17MB82S Only backlight

How can i be sure before the order of the replacement board?

[Dannyx]

Re: Vestel 17MB82S Only backlight

How can i be sure before the order of the replacement board?

Well if it appears to be responding to the remote, I'd most definitely say it's a faulty panel, though it would be nice if you could confirm by "asking" the TV if everything's alright via some sort of interface like someone around here suggested, though I haven't got a clue how you could achieve that without an RS232 interface actually present on the 17mb82s....perhaps someone knows a clever trick or workaround for the purpose....

[tom66]

Re: Vestel 17MB82S Only backlight

17MB62 is similar, I believe


The UART is on pin 10 (TX) and pin 12 (RX). You may need to reverse RX and TX on your UART device. You will also need to connect to the ground of the TV, on pin 4 and 5 for instance, or the chassis.
Make sure to use a 3.3V or 5V UART, not a proper RS232 level device with +/-10V levels which may be fatal to the TV CPU.

[Dannyx]

Re: Vestel 17MB82S Only backlight

How about the CH341 I use for flashing EEPROMs ? I have successfully used that in the past for serial purposes so it should work

[tom66]

Re: Vestel 17MB82S Only backlight

CH341 on its own should work.

[Davi.p]

Re: Vestel 17MB82S Only backlight

Why CH341 should work? I haven't read it has rs232 comm port on it..
I have bought it by ebay but the only info i have is a little specs list on the ebay listing, daoes anyone have a source for the full use of it? That there is something not clear..
thanks..

[Dannyx]

Re: Vestel 17MB82S Only backlight

Why CH341 should work? I haven't read it has rs232 comm port on it..
I have bought it by ebay but the only info i have is a little specs list on the ebay listing, daoes anyone have a source for the full use of it? That there is something not clear..
thanks..

I have successfully used the CH341 to communicate via serial with a router, so I know it can be done. You just have to make sure it's in serial mode and not SPI mode. This stumped me a lot when I first tried it, since despite all sources claiming it CAN do serial interfacing as well, I couldn't get it to show up as a COM port....until I eventually discovered what the little jumper cap on it was for: removed it and I was now in serial mode. The physical layout will differ based on what programmer you get, but the chip itself can do serial via RX/TX....quite versatile IMO.

[Davi.p]

Re: Vestel 17MB82S Only backlight

Thanks for the info and sorry for this OT but if anyone can link to me a page with an user manual i thank him very much 'cause i have a Security Alarm Control Panel board with an ATMEL 24C64AN that doesn't answer to the read function by the programmer.. i have to discover installer code, and there are no indications on what is there for the jumper cap.

[vinceroger69]

Re: Vestel 17MB82S Only backlight

https://onetransistor.blogspot.co.uk...schematic.html

[Davi.p]

Re: Vestel 17MB82S Only backlight

thanks for the info, the jumper meaning is now clear, i found the reason why my ATMEL chip it doesn't read, it works only at 5vcc, i powered it externally and reading's ok and found the installer's code! I'don't know why there's no jumper for 5v/3v selection, i will try to modify that..