Samsung un55c6300 turns itself on and off

[Ttbfat]

Hi, I've got a Samsung un55c6300 with a pd55af1u-zhs PSU. The TV is turning itself back on when turned off with the remote and occasionally shutting itself off when on. We watched it for a while and just unplugged it after use, but this got annoying after a while. I'm trying to fix the problem, but don't want to pay for a new PSU if the issue is somewhere else.. I'd also like to attempt to fix the PSU myself if that's the likely culprit. I pulled the board and checked the voltages with significant help from this thread. The voltages all matched what was expected. I had to jumper 16 and 18 together to confirm. Used an IDE jumper from a computer hard drive, no clue if this was the right way to do it.. I tried to reset the tv to factory defaults, problem still occurs. I'm new to electronics repair, so I'm trying to learn as I attempt to fix this TV. Any help or suggestions would be welcome.

Thanks!

[Ttbfat]

Re: Samsung un55c6300 turns itself on and off

More info.. Well, now the TV is not turning on at all. With the main board and the inverter (?) plugged into the PSU the board is clicking a lot. As I'm checking the voltage on Pin 1, a click occurs, I can see it come up to the normal level (12v) then it shoots back down. Another click, it comes back up to 12v.. With the PSU discconnected from everything and 16&18 jumped together, I'm getting this on the odd pins..

NO MAIN
BOARD
18 PWR On/Off
17 Vamp_18V 17.09
16 STBY_5.2V
15 Vamp_18V 17.09
14 5.3V
13 5.3V 5.19
12 GND
11 5.3V 5.2
10 GND
9 GND 0.0
8 H-Sync
7 GND 0.0
6 PWM_DIM
5 D12V 12.68
4 BLU_On/Off
3 D12V 12.67
2 Vdrv_DET
1 D12V 12.69

[budm]

Re: Samsung un55c6300 turns itself on and off

Is PIN 16 STBY_5.2V staying steady while the relay is clicking? if it is steady then look at Pin 18 (PWR ON/OFF) to see if DCV is swinging up and down.

[tibimakai]

Re: Samsung un55c6300 turns itself on and off

Another C series that clicks.
It seems like, C series suffer from bad mainboards, D series from bad screens.

[Ttbfat]

Re: Samsung un55c6300 turns itself on and off

Well, I've left in unplugged for a couple days. Now when I plug it in, the clicking problem is gone and the screen comes on. If I turn it off, it turns itself back on again. I unplugged the cable to the main board and jumperd 16 and 18 together again. The voltage is staying steady and 5.2V and 18 is not not going up and down.. Do I have a capacitor problem?? Not sure what to do next.. Thanks

[Ttbfat]

Re: Samsung un55c6300 turns itself on and off

Also, there is a rusty red circle on the sheet metal back of the tv. Nothing on the board beneath the circle to indicate a problem. this tv was purchased directly from the installer, wondering if my folks got stuck with a refurb or if it just rusted.. This tv was at a beach house. i'll try to get a pic. thanks again, you guys rock!

[Ttbfat]

Re: Samsung un55c6300 turns itself on and off

pics of rust spot

[freakaftr8]

Re: Samsung un55c6300 turns itself on and off

Could be a button pad issue. Try cleaning the front panel