42LG5000: Service menu - Tool option 1 codes

[saioman]

Hi all! I have been messing around with the service menu of my 42" LG LCD TV. I got there by simultanously pressing MENU on the TV and on the REMOTE for 5-10 seconds. In this menu, there is an option called 'Tool option 1'.

The thing is I've changed the settings there while trying to unlock the USB port for movie playing, and the TV picture went totally bad. After doing some research over the internet, and even downloading the service manual, I found out that each combination of the parameter settings generates a code. Each TV model is supposed to have its unique one.

I know now ... but I didn't write it down ...

Today I did a software update, hoping that it may reset these settings to the right values for my TV, but no luck. Is there any way/place/procedure to find the correct code or parameter configuration for this model? I am attaching the current values within the 'Tool option 1' and the 'System control' menus.

Many thanks in advance!

[tom66]

Re: 42LG5000: Service menu - Tool option 1 codes

Check inside your TV to see what panel it has: AU Optronics, LG Display, Samsung, Chi-Mei, etc. Try matching TOOL OPTION to that panel configuration.

[saioman]

Re: 42LG5000: Service menu - Tool option 1 codes

Ok. I did as adviced and found a sticker on the screen panel, which says as follows:

Manufactured 08/48
Model T420HW02 V.0
AU Optronics XXXXG

The "Tool option 1" is now set to the following values, which seem to match the panel:

Tool option 1 ... 9490
Module ... AUO
Inch ... 42
Tool ... LG5000
Intelligent Sensor ... 1
SRS HD ... 1
Module version ... 0

But no luck. The TV image is still distorted as in the images attached to the first post. Could it be that the settings of the "System control" menu are guilty?
I found the panel's specification, the PDF of which I'm attaching ... but I get lost quite easy there.

Any other thoughts?
Thanks!

[tom66]

Re: 42LG5000: Service menu - Tool option 1 codes

It's not impossible that you have an AS15F Gamma Fault - this can occur randomly... Can you post a picture of your T-con board?

[saioman]

Re: 42LG5000: Service menu - Tool option 1 codes

Sure.

[tom66]

Re: 42LG5000: Service menu - Tool option 1 codes

OK, so on the right of the board near the latching ribbon connector you have a bunch of test points labelled from VGAMA1 to VGAMA22.

With the board installed in the TV can you measure the voltage on each point?

Use a multimeter, digital, 20V DC range (or autoranging DC volt if supported.) Red probe on the test point, black on the chassis. The TV should be on while you do this.

List the results next to each VGAMA point #.

[saioman]

Re: 42LG5000: Service menu - Tool option 1 codes

Since I don't have experience measuring a live TV set, I will ask a friend of mine to help me doing that. Don't want to break anything else if there is still hope to save the TV.
I will send the measurements as soon as I get them. Thanks!

[saioman]

Re: 42LG5000: Service menu - Tool option 1 codes

After a couple of days, my friend took a look at the VGAMAxx test points as suggested. We compared the results with the information in this thread:

https://www.badcaps.net/forum/showthread.php?t=29424

Since the measured voltages looked random, he changed the faulty chip, which I am marking in the attached image. Now everything looks ok and the TV has been working correctly for more than 4 hours.

I'll call this one solved and thank Tom very much for his expert advice.

[tom66]

Re: 42LG5000: Service menu - Tool option 1 codes

That's good to hear, another AS15 fault fixed.