Sanyo FW42D25T

[nomoresonys]

Re: Sanyo FW42D25T

Ok, so probably no boosted voltage in this tv, anyway the panel lights up, 48 leds, 8 across, 6 vertical, all leds are equally bright, then 42 seconds later they all turn off, tested both lines with backlight tester, have 64.5 on both. Kind of seems low if they are 3 volt leds.

[nomoresonys]

Re: Sanyo FW42D25T

After the 42 seconds and they go off, if I try to turn it off and right back on the backlights stay off.

[nomoresonys]

Re: Sanyo FW42D25T

No, I lied, it does come back on, what it does is hit power backlights come on in 5 seconds then go off about 42 seconds later, every time.

[nomoresonys]

Re: Sanyo FW42D25T

Resistor RB114 is marked 4r7 but reading 7.6 ohms, wondering if that would be bad enough to cause this problem.

[nomoresonys]

Re: Sanyo FW42D25T

If you look at the picture in post #1, it's that resistor right there by CB116 by the transformer. Also noticed that the underside of the board where this transistor QB801, located right by the backlight connector is discolored darker than the rest of the board, like it was maybe running hot or something.

[diif]

Re: Sanyo FW42D25T

Resistor RB114 is marked 4r7 but reading 7.6 ohms, wondering if that would be bad enough to cause this problem.

You're measuring it in circuit ? Take it out to measure correctly.

[nomoresonys]

Re: Sanyo FW42D25T

Thanks for reply, guess this model wasn't too popular, very few youtube videos of it. Going to trace it before removing it, see where it goes and see if I can decipher what it does. It's smaller than a grain of rice.

[nomoresonys]

Re: Sanyo FW42D25T

Thinking the problem might be one of those 2 resistors, the other one 200, reads 43 ohms in circuit, or maybe QB101 or CB116.

[nomoresonys]

Re: Sanyo FW42D25T

The most notable thing is, before backlights go off after 45 seconds both UL1 and 2 read correctly, when they go out UL1 still reads correctly but UL2 is dead, any ideas? thanks.

[nomoresonys]

Re: Sanyo FW42D25T

Wondering if UL2 is bad or could it be whatever feeds it voltage is bad, not even any guesses?

[nomoresonys]

Re: Sanyo FW42D25T

Would a bad eeprom UF1 make UL2 read dead/no voltage?

[lotas]

Re: Sanyo FW42D25T

Yes, that might be the case, post your dump here and I'll take a look.

[nomoresonys]

Re: Sanyo FW42D25T

I wish I could Lotus but I'm not smart enough to figure out how it works, I REALLY suffer in this area and most other areas lol. Don't have a programmer, was thinking about grabbing eeprom from m-tronicz, less than 10 dollars, didn't want to invest anything in this seemingly sub-standard tv but I'm just determined to figure out the problem, THANKS for the offer.

[nomoresonys]

Re: Sanyo FW42D25T

Just want to say THANKS, you CapLeaker and Diah are outstanding people who have helped so many, I hope good Karma comes back to you all many times fold.

[nomoresonys]

Re: Sanyo FW42D25T

I left out a few folks who deserve mentioning but they know who they are.

[nomoresonys]

Re: Sanyo FW42D25T

Tested voltages on eeprom 25q32bsig, not sure if it will tell anything or not, tested on bench not grounded, 1-0, 2-3.17v, 3-3.25v, 4-0, 5-0, 6-0, 7-3.28v, 8-3.28v Data sheet: https://www.datasheetcafe.com/25q32bsig-datasheet-pdf/

[nomoresonys]

Re: Sanyo FW42D25T

Ok, off to YT programmer school to try to learn some new tricks.

[nomoresonys]

Re: Sanyo FW42D25T

.

[lotas]

Re: Sanyo FW42D25T

The software in the firmware is live, try it with a clean NVM.

[nomoresonys]

Re: Sanyo FW42D25T

You lost me, you mean I should erase it and try the one you posted above?