JVC 40" LED TV (LT-40KC385) - Turning ON sometimes (stuck on loading, menu etc.)

[netgearnetgear]

Hello esteem members,
I have a JVC Television that fails to turn ON sometimes. The stand-by red light is always on. When the TV turns on the the JVC logo displays then the TV attempts to scan for local channels...it then freezes. If I unplug it, then it refuses to turn on - stand by light on. The power supply input voltages are present - 12V, with the backlight 0.32V when the TV refuses to turn on. Backlight voltage is 2.98V when TV does turns ON. All regulator chip has 3.3V on pin 8. Processor voltage - 1.02V, Ram - 1.5V. I am thinking about reflowing the on-board RAM. When the TV was ON I was able to perform a factory reset but this did not fix the problem. The wifi was connected however youtube, Netflix and the browser did not load - screen went blank (backlight led still ON from the back). The capacitor on the power rail to the Processor has a resistance of 5 ohms which I thought was low but voltage injection at 1V, 2A on the capacitor shows approximately 200mA being drawn. I would like a schematic of this board and any possible guidance in determining the root of hhe problem.

[nomoresonys]

Re: JVC 40" LED TV (LT-40KC385) - Turning ON sometimes (stuck on loading, menu etc.)

Sounds like maybe an eeprom issue on mainboard, try heating eeprom with a hairdryer and or cooling it with inverted can of duster, do not shake the can. I believe the procedure is, tv unplugged from power, cool eeprom, plug tv in and try it, if tv works then it's probably a bad eeprom.

[nomoresonys]

Re: JVC 40" LED TV (LT-40KC385) - Turning ON sometimes (stuck on loading, menu etc.)

Is that model number accurate?

[netgearnetgear]

Re: JVC 40" LED TV (LT-40KC385) - Turning ON sometimes (stuck on loading, menu etc.)

Yes.

[lotas]

Re: JVC 40" LED TV (LT-40KC385) - Turning ON sometimes (stuck on loading, menu etc.)

There is no EEPROM, there is an eMMC, and when it heats up it will die completely!

[netgearnetgear]

Re: JVC 40" LED TV (LT-40KC385) - Turning ON sometimes (stuck on loading, menu etc.)

Ok..thanks. I measured the caps in diode mode around the eMMC (NAND Chip) but none are shorted, so is it safe to assume that the software is corrupted? Do you th8nk I should still reflow the RAM chip?

[EazyBone]

Re: JVC 40" LED TV (LT-40KC385) - Turning ON sometimes (stuck on loading, menu etc.)

When it freezes the backlight stays lit? Trying to understand how voltage to backlight is only 2.98. Like a backlight on pin? Or you measuring the voltage from top right connector?(second pic)

[nomoresonys]

Re: JVC 40" LED TV (LT-40KC385) - Turning ON sometimes (stuck on loading, menu etc.)

There is no EEPROM, there is an eMMC, and when it heats up it will die completely!

I should have stated IF there is an eeprom, I would not suggest heating an eMMC chip, although it would not kill it to heat with a hairdryer, haven't you ever seen them changed out? Exaggerate much? so where do you come off from with that false remark? probably same reason you are always debating with Diah and are usually wrong.

[lotas]

Re: JVC 40" LED TV (LT-40KC385) - Turning ON sometimes (stuck on loading, menu etc.)

I probably same reason you are always debating with Diah and are usually wrong.

Show me at least one topic where I made a mistake when arguing with Diah.

[nomoresonys]

Re: JVC 40" LED TV (LT-40KC385) - Turning ON sometimes (stuck on loading, menu etc.)

https://www.badcaps.net/forum/showth...=117903&page=5 If you want specifics ask him, he would probably be happy to tell you where you were wrong, just keep in mind nobody knows everything, and a hairdryer WILL NOT kill an eMMC.

[lotas]

Re: JVC 40" LED TV (LT-40KC385) - Turning ON sometimes (stuck on loading, menu etc.)

You can read more data (DUMP) from a half-dead eMMC, but if you heat it up, you are unlikely to be able to read anything from it, which is why they read from it without desoldering via the ISP bus in order to save the data, if you have never worked with eMMC, then no need to write nonsense.

[nomoresonys]

Re: JVC 40" LED TV (LT-40KC385) - Turning ON sometimes (stuck on loading, menu etc.)

It's not nonsense, the process of putting them on heats more than a hairdryer, YOU are spitting out nonsense, the end, not debating such a dumb ass statement anymore.

[nomoresonys]

Re: JVC 40" LED TV (LT-40KC385) - Turning ON sometimes (stuck on loading, menu etc.)

Truth is you may know more about dumps BUT it's no contest, Diah has you beat by a long shot in every other aspect of tv repair.

[lotas]

Re: JVC 40" LED TV (LT-40KC385) - Turning ON sometimes (stuck on loading, menu etc.)

I doubt it, and what does Diah have to do with it if we are talking about your knowledge.

[netgearnetgear]

Re: JVC 40" LED TV (LT-40KC385) - Turning ON sometimes (stuck on loading, menu etc.)

When it freezes the backlight stays lit? Trying to understand how voltage to backlight is only 2.98. Like a backlight on pin? Or you measuring the voltage from top right connector?(second pic)

Hello, the voltage is on the power connector pin. See pic attached. O.32V when the TV is off and 2.98V when the TV is on.

Update: I reflowed the NAND chip, however, it made no difference.

[lotas]

Re: JVC 40" LED TV (LT-40KC385) - Turning ON sometimes (stuck on loading, menu etc.)

eMMC has its own life (resource), wear and tear from rewriting cells.

[netgearnetgear]

Re: JVC 40" LED TV (LT-40KC385) - Turning ON sometimes (stuck on loading, menu etc.)

Noted....regards

[nomoresonys]

Re: JVC 40" LED TV (LT-40KC385) - Turning ON sometimes (stuck on loading, menu etc.)

I doubt it, and what does Diah have to do with it if we are talking about your knowledge.

pm sent.

[Topcat]

Re: JVC 40" LED TV (LT-40KC385) - Turning ON sometimes (stuck on loading, menu etc.)

Unless anyone here is still in junior high, the bickering will stop. If your an adult with a gearbox stuck in junior high, I'll just hand out bans. If I have to come back, the thread is just going to disappear.

[nomoresonys]

Re: JVC 40" LED TV (LT-40KC385) - Turning ON sometimes (stuck on loading, menu etc.)

You mention jr. high quite often, was that a difficult time for you? I'm so SORRY if it was, it wasn't for me but for some it can be a painful experience.