Sharp Aquos 32"

[rigeback]

Re: Sharp Aquos 32"

All the tests were good except for BU 1.8V and BU+1.8V lines seems to have a problem there is only 1.78 Volts on these test points so I think one of the IC's might be bad.
I cross checked IC 1756 and find Pin1=1,21V Pin3=3.04V Pin4=3.22
Pin5=1.79V
I also tested IC 1702 ; pin1=1.21V pin3=3.04V pin4=3.22V and pin5=1.79VOn IC 1726 pin2=8.16Vas with pin3=8.16V so some where in between theres a malfunction if this 8 Volt line supplies the screen?
This link might might help trouble shoot the problem.
http://www.scribd.com/doc/67258779/S...urse-English-1

[momaka]

Re: Sharp Aquos 32"

Looks like all of the major t-con voltages are there then. So t-con is likely working fine.

There are some other voltages not on the t-con that are probably worth checking, though. These are (using the same 3rd picture in post #9 as a reference) test points:
BU 3.3V, B+5V, BU1.8V, B+3.3V, and VCC3.3V

[rigeback]

Re: Sharp Aquos 32"

Yes you caught me out again, set the tester on 200V and sure enough 35V is present on
VGH35V and yes the "1" was there for resistance test, IC8402 has "DCQG" printed on top in large letters, the outer pins have 30V and the center pin has 35V.
I found a good pdf manual that I wanted to upload but it won't load even so it only 5MB.
Compliments of the season and the site looks great with the Christmas lights!

[momaka]

Re: Sharp Aquos 32"

VLS15.6V and VCC1.5V are good.
The voltage on VGL-6V is good as well. I'm not sure the resistance you measured is correct, though. 5 Ohms would suggest that rail is supplying over 1 Amp of current, which is not possible since these secondary step-up rails are low-current. Anyways, since the voltage is correct, I'm inclined to think everything is fine with that rail.

VGH 35V on the otherhand has no power and no resistance.

What do you mean by no resistance? Is the multimeter showing 0.00 Ohms or a "1" (or "OL") on the left side of the screen?
- If "1" (or "OL") on the left side of the screen, that's fine.

Also, VGH35V will likely measure close to 35V, so with a manual multimeter make sure to use the 200V scale and not the 20V scale when measuring the voltage. Otherwise you will get a "1" or "OL" on the left side of the screen.
If you still don't get any voltage even after trying that, try measuring the voltage on all of the pins of Q8408.

Lastly, what is the part number on IC8402?

[rigeback]

Re: Sharp Aquos 32"

VGH35V connects with Q8408 and D8408 and further I did not find a connection

[rigeback]

Re: Sharp Aquos 32"

Hey Momaka, good to have you trouble shooting again! Lets hope I get this one right.
Anyways these are the resuls of the tests; VLS 15.6V seems good with 15.55 Volts, [B]VCC1.5 v = [B]100 Ohms and with power on read 1.49 Volts. VGH 35V on the otherhand has no power and no resistance.
VGL 6V also has very low resistance at 2K 5.0 Ohms and a negative power reading -5.97 Volts.
I will try see what VGH 35V connects with.

[momaka]

Re: Sharp Aquos 32"

theres a bunch of FB and FL type fuses but they check out ok so far

FB is probably an abbreviation for Ferrite Bead (in other words, an inductor).
FL - Ferrite Inductor?? I'm guessing though.

Looks like Scenic is right - this TV combines the t-con with the video board. If you look at the 3rd picture in post #9 (this one), you can see test points VGH35V and VGL-6V in the lower right corner near the large connector and the big Sharp microchip. VGH and VGL are names usually associated with the secondary step-up rails on a t-con. My guess is that VLS15.6V is the primary step-up rail.

Like other LCD monitors we've tested before, measure the resistance between VLS15.6V and ground, VGH35V and ground, and VGL-6V and ground. I think you already know the drill here - use 200 Ohm scale (the lowest one).
Also measure the voltage on the VLS15.6V rail. Should be 15.6V if everything is right (or if the label on the circuit board is correct).

[Scenic]

Re: Sharp Aquos 32"

Looking at the last pic in the first post, it looks like Sharp decided to combine the t-con and the mainboard on one PCB for some stupid reason (cost saving?)

I marked it in red in the attached picture. The bundle of traces going from the chip with the heatsink on it (CPU?) to the chip above it is probably where "normal" LCD TVs would have a cable running to a seperate T-Con board mounted at the top center of the panel. But instead, it's all on the mainboard, so if one thing fails, the whole mainboard has to be replaced if it can't be fixed.

Good to know. I'll stay away from Sharp LCD TVs then. What a POS. [/rant]

[rigeback]

Re: Sharp Aquos 32"

Yes I have been looking for that F1 fuse but I don't see it on this board or the T-con, theres a bunch of FB and FL type fuses but they check out ok so far, theres some new pics but not so clear of the T-con.
This type of control board has incorporated most of the t-con parts it seems.

[retiredcaps]

Re: Sharp Aquos 32"

Post a picture of the t-con. If there is a fuse, check to see if it is open. A good fuse should measure less than 1.0 ohms.

[rigeback]

Re: Sharp Aquos 32"

Hi guys, any info as to where to get started here would be great, could it be the T-con because the PSU seems to be okay although I will recheck the voltages before I go a head and dissassemble the unit, power stays on normal and I can listen to CNBC, the back lights are working but I can't enter setup or do factory reset. I found a good data sheet for the boards, please see attached.

[rigeback]

Re: Sharp Aquos 32"

Well the TV has definetly got a picture problem as it didn't show the desk top of the laptop connected two ways, some part will have to be changed, a web search reckons the inverter needs new parts but think this one has an easier solution, hopefully.

[rigeback]

Re: Sharp Aquos 32"

Hi Bill. Yes, and its a 26" as I just noticed, looking at the manual just now, what do you think wrong with it??

[PlainBill]

Re: Sharp Aquos 32"

I found this TV at the Dumpster today and seeing it had never been opened brought it home to try it out, unfortunately I didn't find the remote!
The power supply seems to be working okay as with the back lights and sound although when I tried to enter setup manually theres nothing.
I have not hooked it up to the sat decoder as yet but I'm sure they wouldn't have thrown it away if they had a picture!
I am considering to hook it up the a PC first as soon as I've down loaded more info from Sharp, would appreciate any good recommendations as where to start as this is my first plasma!!

It's an LCD, not a plasma.

PlainBill

[rigeback]

Re: Sharp Aquos 32"

I tried hooking it up to my sat decoder via SCART cable and I have sound but no picture, I do not have an antena with the single M/F plug, will try to the PC later but I want to read the manual a bit reagrding firmware etc.

[retiredcaps]

Re: Sharp Aquos 32"

would appreciate any good recommendations as where to start as this is my first plasma!!

Look at your last picture with the logic board. CCFL in LCD panel.

Anyway, hookup a source and report back what you find.

[rigeback]

I found this TV at the Dumpster today and seeing it had never been opened brought it home to try it out, unfortunately I didn't find the remote!
The power supply seems to be working okay as with the back lights and sound although when I tried to enter setup manually theres nothing.
I have not hooked it up to the sat decoder as yet but I'm sure they wouldn't have thrown it away if they had a picture!
I am considering to hook it up the a PC first as soon as I've down loaded more info from Sharp, would appreciate any good recommendations as where to start as this is my first plasma!!