Grundig 55 GUB 8860 - bad T-Con or bad panel?

[Diah]

Re: Grundig 55 GUB 8860 - bad T-Con or bad panel?

the way you did GPU use the same Temp ca 250 !! and time

[Ierwin]

Re: Grundig 55 GUB 8860 - bad T-Con or bad panel?

I don't remember what Temperature I used back then, it's been 15 years.
Some sites suggested starting at 100°c and working up from there so that's what I'll do
As far as I remember you can't really reach a temperature where the solder completely melts without proper tools, only enough for it to get soft and possibly regain connection.
Will report my results

[Ierwin]

Re: Grundig 55 GUB 8860 - bad T-Con or bad panel?

Oh if you or anyone else has a chance to get their hands on the correct panel.bin I would still be very interested. As far as I understand I could use a replacement Mainboard from a TV with a different panel then so it would be way easier to find a used part

[Diah]

Re: Grundig 55 GUB 8860 - bad T-Con or bad panel?

Oh if you or anyone else has a chance to get their hands on the correct panel.bin I would still be very interested. As far as I understand I could use a replacement Mainboard from a TV with a different panel then so it would be way easier to find a used part

can you measure the reading of the small parts connected to pin 44 ? lvds most disconnected during measurements

[Ierwin]

Re: Grundig 55 GUB 8860 - bad T-Con or bad panel?

Do you mean this tiny C? With all cables disconnected I'm reading 0V.
Might be short but didn't check for other parts in parallel yet

[Diah]

Re: Grundig 55 GUB 8860 - bad T-Con or bad panel?

it is L not C so it read continues ?

[Ierwin]

Re: Grundig 55 GUB 8860 - bad T-Con or bad panel?

Yes,if it is L it's okay

[Ierwin]

Re: Grundig 55 GUB 8860 - bad T-Con or bad panel?

I went up until 200°C with the oven and left the board in for 10 minutes.
No change at all and I fear if I go higher the plastic ob the connectors could melt.

[Diah]

Re: Grundig 55 GUB 8860 - bad T-Con or bad panel?

200°not enough..in the factory when they apply the soldering pasta first and then the components , it move to the oven which first step 200 then to 310 then back to 150 to the cooling station. t´he worry you have about sockets you can apply kitchen aluminum paper to shape it like cups to cover them. put don't let the paper touch them. this is the packing which i use. beside other method to use Korean in room infrared grill if i want to go only on specification area / chips

[Ierwin]

Re: Grundig 55 GUB 8860 - bad T-Con or bad panel?

Its time to give up unless I find a really cheap mainboard I think.
Thank you for the help, I have now taken it to the point where the mainboard is definetly toast.
I thought it would be smarter to heat up the main chip with a heatgun on low blow setting, while I monitored the chips temperature with an infrared thermometer. Slowly heated it up until the surface reached 250 very briefly, then went down to 190 then let it cool.
That killed it.

Now when I plug the set in, the PSU makes a humming noise and the blue led is no longer blinking

[Diah]

Re: Grundig 55 GUB 8860 - bad T-Con or bad panel?

I thought it would be smarter to heat up the main chip with a heatgun on low blow setting, while I monitored the chips temperature with an infrared thermometer. Slowly heated it up until the surface reached 250 very briefly, then went down to 190 then let it cool.
That killed it.

what ...??we didn't mentioned at all to use hot air gun.. however if some one read this thread in case using normal hot air gun we should cover the chips and all components around with type to avoid one of them move or flying out. and this what happen now.