sharp LC40ELE 600E standby only faulty backlight

[jimbofz]

Re: sharp LC40ELE 600E standby only faulty backlight

Damn what a sensitive tv, wonder if there's a way to adjust the sensitivity that's making it shut down, not disable of course because it's definitely needed for safety.

i trawled the net to find such a thing ,no luck
perhaps someone out there knows a way to desensitise the error protection
.i studied the cct for hours

[nomoresonys]

Re: sharp LC40ELE 600E standby only faulty backlight

Damn what a sensitive tv, wonder if there's a way to adjust the sensitivity that's making it shut down, not disable of course because it's definitely needed for safety.

[jimbofz]

Re: sharp LC40ELE 600E standby only faulty backlight

one of the replacement leds decided to go s/c
just replaced it ,maybe ,me being an optomist ,
i may have heated it up too much when fitting
tv now comes in and out of sby no problem ,its now ot soak test

[jimbofz]

Re: sharp LC40ELE 600E standby only faulty backlight

PROGRESS the 9v leds arrived from China .once replaced ,yes you guessed it same symptom
and still refusing to enter s mode
so i removed one of the original strips ,and one of the repaired ones, then fed them from b/l tester to compare volts and current drawn (on test bench)
there was a 3v difference .
the repaired strips were 170v
the original were 173.2 v
just as experiment i added one 3v led to each of the repaired strips
and now i can enter s mode
i have to tidy up strips and glue lenses back on and will run it for hours before refitting screen ,then im hoping i can clear the lamp error detection
the original leds when tested in tv (not with b/l tester ) have 10v across them and the replacements have 8.9v this makes me think that the original ones are 10v not 9v .
for the cct to work properly each strip must draw the same current ,and have same volts across .
and its a very sensitive design that compares each of the 9 strips im now taking a break from this headscratcher .but will update final results ive just noticed one led not lit ,i will look into it and post back
i may try to buy some 10v leds if they are available.as i dont like giving up

[nomoresonys]

Re: sharp LC40ELE 600E standby only faulty backlight

Strange that doesn't work, lotas has the procedure step by step, head scratcher for sure.

[jimbofz]

Re: sharp LC40ELE 600E standby only faulty backlight

Sharp TV - error reset!



There are many TV Sharp models that have a memory lock on the motherboard. When the backlight or power supply fails and the TV is turned on 5 times or more, the lock will turn on.

And even if you repair the faulty nodes, the TV will not turn on. In this case, the network indicator flashes first green and then red.



Description of how to restore the TV.

1. Unplug the power cord while holding the source button (AVTV) and the volume down button.

2. Insert the plug into the socket (without releasing the buttons held before).

3. When the screen appears, release the buttons.

4. The letter K will appear on the screen. This is the factory debug mode. In this mode, there are only two levels of volume up and down: 15 and 30.

5. Press and hold V - and CH. - simultaneously. The English menu will appear.

6. Using the arrow buttons on the TV remote control, switch to the second page of the menu.

7. On the first column of the second page, click - reset to factory settings. Or, in some models, select the item "ERROR NO RESET" (error reset, the number is equal to the number of faults) .Reset errors.

8. Then unplug the power plug.

TV should turn on.

thanks lotas
i need to get into s mode first
i dont give up

[jimbofz]

Re: sharp LC40ELE 600E standby only faulty backlight

This should work, make sure there's no status light on, on front of tv. Hold volume down and source button both keep holding hit power button, keep holding the volume- and source button til it comes on, then press volume down and channel down, screen should come on, look for lamp errors, there will probably be 5 of them.

tried that 100 times still cant enter s mode .as mentioned earlier im waiting for 9v leds from china ,hoping when fitted i can enter s mode ,supplier confirms they are now in the uk
i will post the results thanks to all those trying to help

[lotas]

Re: sharp LC40ELE 600E standby only faulty backlight

Sharp TV - error reset!



There are many TV Sharp models that have a memory lock on the motherboard. When the backlight or power supply fails and the TV is turned on 5 times or more, the lock will turn on.

And even if you repair the faulty nodes, the TV will not turn on. In this case, the network indicator flashes first green and then red.



Description of how to restore the TV.

1. Unplug the power cord while holding the source button (AVTV) and the volume down button.

2. Insert the plug into the socket (without releasing the buttons held before).

3. When the screen appears, release the buttons.

4. The letter K will appear on the screen. This is the factory debug mode. In this mode, there are only two levels of volume up and down: 15 and 30.

5. Press and hold V - and CH. - simultaneously. The English menu will appear.

6. Using the arrow buttons on the TV remote control, switch to the second page of the menu.

7. On the first column of the second page, click - reset to factory settings. Or, in some models, select the item "ERROR NO RESET" (error reset, the number is equal to the number of faults) .Reset errors.

8. Then unplug the power plug.

TV should turn on.

[lotas]

Re: sharp LC40ELE 600E standby only faulty backlight

Lamp error detection
1. Function description
This LCD colour television has a function (lamp error detection) to be turned OFF automatically for safety when the lamp or lamp circuit is abnormal.
If the lamp or lamp circuit is abnormal, or some other errors happen, and the lamp error detection is executed, the following occur.
1) The main unit of television is turned OFF about 5 seconds after it is turned ON.
(The power LED on the front side of TV turns from green to red.)
2) If the situation “1” happens 5 times sequentially, the power is turned on (relay is turned ON).
However, the backlight is not turned on, and then the relay is turned OFF after 5 to 6 seconds. (The power LED remains red.)
2. Countermeasures
When television is turned OFF by the lamp error detection mentioned above, it enters the adjustment process with the power LED red.
Entering the adjustment process, turns OFF the error detection and turns ON TV.
This enables the operation check to detect errors in the lamp or lamp circuit.
Check whether “STANDBY CAUSE” on line 7, page 1/8 of the adjustment process is “1B”. it indicates the lamp error detection was executed.
After confirming that the lamp or lamp circuit is normal, reset the lamp error counter pushing “OK” in the R/C.
After resetting counter the green bar appears on Screen.
3. Reset standby cause error list
After confirming that the lamp error counter has been erased, select “ERROR RESET”, page 1/8 of the adjustment process and select YES using
the right cursor. For execute press “OK” in the R/C and the label “***OK***” appears on Screen.

[nomoresonys]

Re: sharp LC40ELE 600E standby only faulty backlight

This should work, make sure there's no status light on, on front of tv. Hold volume down and source button both keep holding hit power button, keep holding the volume- and source button til it comes on, then press volume down and channel down, screen should come on, look for lamp errors, there will probably be 5 of them.

[nomoresonys]

Re: sharp LC40ELE 600E standby only faulty backlight

Good question, might have to reprogram a chip or something.

[Yanleb]

Re: sharp LC40ELE 600E standby only faulty backlight

Some of you don't understand that you cannot access the service menu if the TV set refuses to power on due to the lamp error. After getting the lamp error 5 times it locks down indefinitely. In that case all the key combinations you can read in the service manuals will just not work.

In my case the LED strips were repaired but it has been impossible to bring the service menu to reset the lamp error. An oscilloscope in single trigger mode on the LED driver circuit proved that.

The TV doesn't have a crystal ball. It has to power on the backlight to detect if it is working or not. After 5 tries with bad LED strips the TV will just abandon and will never try again.

[lotas]

Re: sharp LC40ELE 600E standby only faulty backlight

Reset "error lamp" can be done through the service menu.

[Yanleb]

Re: sharp LC40ELE 600E standby only faulty backlight

When you power on the TV set, do you see at least an attempt to power on the backlight? If yes, there's still something the LED driver doesn't like.

If you plug in the TV set and it immediately starts to blink the lamp error code, then it likely reached the 5 tries and it is now locked indefinitely in the lamp error mode.

You already found my thread about another Sharp TV set stuck in the lamp error mode:
https://www.badcaps.net/forum/showthread.php?t=98411

On my TV set a sub processor was handling the lamp error, and this error can be cleared by erasing the small eeprom attached to it (IC2004). The difference is that your TV set seems to have the lamp error detection in the main processor, not in a sub processor. This means that erasing the eeprom will clear a lot more data than it did for me.

As you said in my thread it seems that the eeprom to erase in your case is IC8455. I would suggest that you backup its content before erasing it. In the case it doesn't solve your problem just restore its content. The BR24S64F is available here: https://www.mouser.co.uk/c/?q=BR24S64F

Or you can probably substitute it by another 24C64 compatible eeprom if you don't want to erase yours (after backing it up).

Another option is to look around for an eeprom dump of IC8455. You can also make a request for it in the eeprom dump section of this site.

As a last resort (I did it a few times), just buy a replacement board from eBay, backup the content of IC8455 and sell back the board on eBay. Just confirm with the seller that the board is indeed working and was not removed from a TV set with a backlight issue.

You will lose the shipping fees but it is not that bad. Just be kind and upload the dump file to help people in the future.

[jimbofz]

Re: sharp LC40ELE 600E standby only faulty backlight

It does look like the VLED voltage is around 170v. The power supply raw supply voltage is likely around 150V (C7528) then gets boosted by Q7506 to a higher voltage (C7525)
So if there are 17 leds per string, 9v led's would make sense.

with psu forced on and p on fed with 5v
theres no bl-on from cn7603 pin 2 .
so q7509 and q7511 (b/l switch ) off.
so no boosted vled volts from q7506
the v led volts across c7528 is the same as across c7625.
the 13v supply to ic 7506 pin6 is present
any thaughts please
i keep trying to enter s mode with no luck
im wondering if i should try a f/w update this may then allow s/mode entry
do you think that may work?

[jimbofz]

Re: sharp LC40ELE 600E standby only faulty backlight

It does look like the VLED voltage is around 170v. The power supply raw supply voltage is likely around 150V (C7528) then gets boosted by Q7506 to a higher voltage (C7525)
So if there are 17 leds per string, 9v led's would make sense.

ive just tested the current drawn by each strip,
when fed externally via b/l tester
on the 2amp range its ,042amp
and to my surprise its the same on all strips including the ones i have fitted the replacement 6v type leds
so now im thinking there must be a fault in the lamp error detection cct .im going to have a closer look at the supplies around this
i do know about the "5 strikes and your out "
but to clear you need first to be able to enter s/mode

[R_J]

Re: sharp LC40ELE 600E standby only faulty backlight

It does look like the VLED voltage is around 170v. The power supply raw supply voltage is likely around 150V (C7528) then gets boosted by Q7506 to a higher voltage (C7525)
So if there are 17 leds per string, 9v led's would make sense.

[jimbofz]

Re: sharp LC40ELE 600E standby only faulty backlight

6 out of 9 strips are perfect complete with original leds when connected separately each strip measures 172v ,from this i assume that each strip is drawing the same current
now the 3 remaining strips ,
just as an experiment
i added an extra led to each strip because they had 167v across them
they now have 173v across them .within tollerance i think?
after trawling the net i found a supply of 9v leds as used in sharp ,
so there ordered from china so will take some time to arrive.
from reading the s manual i found that when in service mode it should be able to
clear the error detection and reset standby cause
but it refuses to enter s mode so its catch 22
thanks for your help
i will try measuring the current drawn by each strip when fed with b/l tester to see if theres any variation

[R_J]

Re: sharp LC40ELE 600E standby only faulty backlight

The circuit monitors the current for each led line, If the led's you installed are wrong then the current will be wrong. They might be 3v led's I don't know.

[jimbofz]

Re: sharp LC40ELE 600E standby only faulty backlight

I suspect your meter is not reading the voltage across the led's correctly, The drive for the leds has a high frequency component and your meter is reading that as well as the dc value.

thats something i would never have thaught of.
i replaced the faulty ones with 6 volt types used in LG models
and with my meter i read 6 v across the replacements
as it wont allow service mode ,is there any way to desensitise the protect cct just to allow s/m access
then according to manual i can reset the error codes
(more than 5 errors and tv locks up with just s/b lit)
ive tried many times to enter s/m no joy