Sharp Aquos LC-32GD8E

[tom66]

Re: Sharp Aquos LC-32GD8E

Maybe. Check all voltage regulators, power supplies on main board.

[gilly1984]

Re: Sharp Aquos LC-32GD8E

I can get the relay to click when i put 3.3v on both pcons1&2, This then gives me a nice speaker pop like a normal tv would do and i get 24v going to the inverters, but no lights yet.

Checked all diodes and transistors on the mainboard but all seem ok.

[tom66]

Re: Sharp Aquos LC-32GD8E

Jump INV-ON to get backlights to fire up.

If screen is good then (not cracked) replace main board I guess... Or hunt down a set with a cracked LCD.

[gilly1984]

Re: Sharp Aquos LC-32GD8E

what voltage should blon be? tried jumping all 3 coz they are next to each other with the same 3.3v but relay clicked off.

[tom66]

Re: Sharp Aquos LC-32GD8E

Hmm, that is strange, but try using a 1kohm resistor instead between 3.3V and BLON/INV ON.

If that does not work you will have to break out the wire from the inverter and feed 3.3V in that way.

[gilly1984]

Re: Sharp Aquos LC-32GD8E

Can i use the 3.3v from a pc psu to do this or should i carry on using a 3.3v source from the tv mainboard?

Would the inv_brt be jumped too? I am guessing this controls the brightness.

Thanks Tom.

EDIT,

Woops, just noticed that BLON is actually pin 4, and not 3. Pic included.

[budm]

Re: Sharp Aquos LC-32GD8E

Just remember one thing about trigerring the PS_ON, BL_ON, these signals are generated by the main board, the output are from the Collector of the transistors on the main board that is normally on so the output will be low until the micro controller turns off the transistors so that the transistors will switched off causing the signals to go high. If the transistors are on, when yoy try to jump the PS_ON or BL_ON Pin, nothing will happen since the transistors are on (stay in LOW state). You should disconnect the BL_ON, PS_ON lines that go back to the main board before using the resistor to force on the inverter and the power supply.

[gilly1984]

Re: Sharp Aquos LC-32GD8E

I have got the screen to come on by jumping pcon1, pcon2, inv_on and inv_brt, all whilst connected to the main board. The screen lit up but had lines down it, they started from about halfway down the screen then to the bottom of the screen, dont think it it tab bond issue as it wasnt all the way down the screen.

Here is some pics of the mainboard, in the service manual it says BU5V goes to 2 voltage regs, a 3.3v and 1.8v reg but i cant find them to test them?

[tom66]

Re: Sharp Aquos LC-32GD8E

Sounds more like a T-con not getting proper power or main board crashing -- may be quite normal... I have seen weird patterns before when getting screen to light up with main board dead.

[gilly1984]

Re: Sharp Aquos LC-32GD8E

Can you spot any voltage regs to test Tom? Or point me in a direction to test something.

I dont like to give up on things

Just throwing a null modem together but read that you can only send commands to a tv that is on? Is this true, if it is i am doomed.

Thank for input budm.

[tom66]

Re: Sharp Aquos LC-32GD8E

The 5 pin plus tab devices in this pic are all regulators.
https://www.badcaps.net/forum/attach...0&d=1354726268

I have never seen a bad Sharp regulator, but I would not rule it out.

[gilly1984]

Re: Sharp Aquos LC-32GD8E

How do i test them, one has 3.3v on the tab, but the other 2 have 0v

2 have 5.2v on pin 1 and the 3rd one has 15.6v on pin 1.

[tom66]

Re: Sharp Aquos LC-32GD8E

Test all pins & list part number... test relative to chassis of TV with TV plugged in.

[gilly1984]

Re: Sharp Aquos LC-32GD8E

I cant use chassis ground as regs are on the underside of the mainboard, i used the screw hole on the hdmi instead.

Datasheet http://pdf1.alldatasheet.com/datashe...0WZ11J00H.html

Reg 1 (ic1702) Tab at top,

pin 1 = 5.14v
pin 2 = 3.71v
pin 3 = 3.29v
pin 4 = 2.62v
pin 5 = 0.00v

Reg 2 (ic1707) Tab at top,

pin 1 = 5.23v
pin 2 = 0.00v
pin 3 = 0.00v
pin 4 = 0.00v
pin 5 = 0.00v

reg 3 (ic1703) Tab at top,

pin 1 = 15.67v
pin 2 = 0.00v
pin 3 = 0.00v
pin 4 = 0.00v
pin 5 = 0.00v

Also there is a 5 pin smd too, it is marked with ZG6F35, google doesnt help with that one.

I will give readings anyway,

Location, ic1701

pin 1 = 3.73v
pin 2 = 5.19v
pin 3 = 0.00v
pin 4 = 0.00v
pin 5 = starts off at 1.70v ish then quickly drops to 0.46v, it does that every I i touch it with the probe, its like the probe is putting a drain on it?





rs232 lead is no good, the link you sent me says that it only works on a tv that switches on

[tom66]

Re: Sharp Aquos LC-32GD8E

OK, thanks for readings.

Pin #1 is input.
Pin #2 is enable control for output (>2V, output on)
Pin #3 is output.
Pin #4 is adjustment terminal (should be 2.64V, relative to GROUND)
Pin #5 is ground.

pin 1 = 5.14v
pin 2 = 3.71v
pin 3 = 3.29v
pin 4 = 2.62v
pin 5 = 0.00v

Working: Output is enabled, 3.3V out, with adjustment at ~2.64V.

pin 1 = 5.23v
pin 2 = 0.00v
pin 3 = 0.00v
pin 4 = 0.00v
pin 5 = 0.00v

Working: Output is disabled.

pin 1 = 15.67v
pin 2 = 0.00v
pin 3 = 0.00v
pin 4 = 0.00v
pin 5 = 0.00v

Working: Output is disabled.

For other regulator, the readings seem odd. Picture?

[gilly1984]

Re: Sharp Aquos LC-32GD8E

Ok, thank you.

Here is pic. Not sure what it is so gave readings anyway.

What is it that tells the regs to switch on?

Can i switch them on by jumping or will that kill something.

[gilly1984]

Re: Sharp Aquos LC-32GD8E

When i jump the blon/pcon 1 &2 the other regs start working. ic1707 gives 3.3v on the outpu, and ic1703 gives 8.00v on the output.

Is there a way to reset the bios chip? (Not bios but you no what i mean).

There is 2 solder points on the mainboard too that say "TP RESET" but this does nothing.

[tom66]

Re: Sharp Aquos LC-32GD8E

Probably not a regulator.
I think firmware may be corrupt, no reset will cure that. The "I2C" method may be necessary...

[gilly1984]

Re: Sharp Aquos LC-32GD8E

Can i make my own interface?

[tom66]

Re: Sharp Aquos LC-32GD8E

It looks like the Sharp board has custom IC on it, so probably not, plus you would need new firmware. Right now I think you should look for a new main board.