Samsung UE46C6005 clicking, no start

[PowerAmpFreak]

Samsung UE46C6005 just clicking, doesn't start.
Does those newer models also suffer from bad caps, just like the LE series?
Opened it up and checked this ultra thin powersupply, without finding any bulging caps.

[tom66]

Re: Samsung UE46C6005 clicking, no start

This is LED backlit.
Not usually suffering from bad caps. However, you need to make some tests. For example, if the PS ON is unstable... suspect the main board or a shorted t-con.

[PowerAmpFreak]

Re: Samsung UE46C6005 clicking, no start

It appears to be some problem with the T-con, I measured only 1V at T-con fuse F1 (fuse ok).
Wonder what normally blown on those T-cons? I will check in detail.

[budm]

Re: Samsung UE46C6005 clicking, no start

The B+ connection that feeds the fuse on the T-CON will be fed through a switched MODFET on the main board, you can trace out which pin is the B+ pin for feeding the T-con board. When you find that pin connection, then remove the cable between the TC-ON and the main board to see if you will get either 5 or 12vdc on that pin on the main board.

[PowerAmpFreak]

Re: Samsung UE46C6005 clicking, no start

Very interesting info, Budm. I will check this out.
What is the most common fault on those, t-cons or mainboards?

[tom66]

Re: Samsung UE46C6005 clicking, no start

In my experience, ceramic caps and shorted controller ICs.

[PowerAmpFreak]

Re: Samsung UE46C6005 clicking, no start

Mainboard used a SI4435 P-FET to power T-Con. The FET does recieve 12V, but the gate is never activated. So mainboard doesn't want to power the T-Con obviously.
I hate those corrupt mainboards.

[tom66]

Re: Samsung UE46C6005 clicking, no start

Or the fet has a drain-gate short, have you tried manually triggering it?

[PowerAmpFreak]

Re: Samsung UE46C6005 clicking, no start

Or the fet has a drain-gate short, have you tried manually triggering it?

Not yet, I will check this more on Tuesday. Thanks for all your advice guys!

[PowerAmpFreak]

Re: Samsung UE46C6005 clicking, no start

No failure to FET SI4435 so it boils down to other mainboard problem. I wish I could factory reset or rewrite those damn eeproms.

[tom66]

Re: Samsung UE46C6005 clicking, no start

Probably actually the flash on the board that gets corrupted. Hence the reason it boot loops. The mini-kernel boots and turns the PSU on, getting all the rails ready. (This resides in the ROM on the main processor usually.) Then, the main kernel (usually Linux on these) is decompressed and booted. If the kernel fails to boot for any reason (or decompression fails), you get a boot loop. It would be nice if the UART could be broken out and we could see the kernel messages; I'm not sure if that's possible on these TVs.