Samsung UE40F6320AK on / off boot loop problems

[Bloopeta]

Hi,
I have a Samsung UE40F6320AK stuck in boot / start up loop when I turn it on it boots up to the logo screen then shuts itself of and back on again continuously.

I have removed the back, and no obvious bad capacitors, I have unplugged and cleaned all cables and connectors

I have tried isolating parts individually, I tried unplugging wifi module, bluetooth module, power button/remote sensor, to no avail.

I tried unplugging Tcon, exact same prob. Cable to backlights etc.

The only time anything differs is, if I unplug video board from power board, it still loops on and off, however it does it twice as fast.

When I unplug the main power cable from the TV, it still clicks as if turning on and off for a few seconds, aprox 3 or 4 times, before it actually becomes silent.

Any help where to start with this or where to end with it greatly appeciated.

[budm]

Re: Samsung UE40F6320AK on / off boot loop problems

Lets see good clear pictures of the whole backside of the TV showing all the boards so we can see what we are dealing with.

[Bloopeta]

Re: Samsung UE40F6320AK on / off boot loop problems

Thankyou for your reply.
Here are the pics as requested, if you require anymore please let me know.

[nomoresonys]

Re: Samsung UE40F6320AK on / off boot loop problems

Could try eeprom reset, hold a wire from EEPROM_GND to EEPROM_SDA power up tv for about 20 seconds remove wire then turn tv off, so for reference we will say that FA_TX is number 1, you want the wire on numbers 4 and 6 which is eeprom-gnd and eeprom-sda. DO NOT PUT IT ON FA_TX.

[Bloopeta]

Re: Samsung UE40F6320AK on / off boot loop problems

Could try eeprom reset, hold a wire from EEPROM_GND to EEPROM_SDA power up tv for about 20 seconds remove wire then turn tv off, so for reference we will say that FA_TX is number 1, you want the wire on numbers 4 and 6 which is eeprom-gnd and eeprom-sda. DO NOT PUT IT ON FA_TX.

Have tried this, made no difference

[raydem]

Re: Samsung UE40F6320AK on / off boot loop problems

Could you re-program the eeprom? It is like the eeprom is corrupt.

[Bloopeta]

Re: Samsung UE40F6320AK on / off boot loop problems

Could you re-program the eeprom? It is like the eeprom is corrupt.

I wouldnt know where to start lol

[Bloopeta]

Re: Samsung UE40F6320AK on / off boot loop problems

Would it be the eeprom though? As if I unplug the main cable prom the PSU to video board, its still does the same??

[Bloopeta]

Re: Samsung UE40F6320AK on / off boot loop problems

Not sure if its worth mentioning, but before trying eeprom reset, after plugging TV in, it would go into standby, and I would have to turn on via remote or power button to get it to the looping stage, however after attempting eeprom reset, now as soon as the TV is plugged in, it tries to start automatically without having to press anything.

[yokoono]

Re: Samsung UE40F6320AK on / off boot loop problems

Put the TV in the socket and immediately put on the nand memory with freeze spray (-55 celsius degrees). You have a chance to get out of the loop. Then do a factory reset.

[Bloopeta]

Re: Samsung UE40F6320AK on / off boot loop problems

I have tested power board outputs without anything pluged into power board, the results when it clicks are

1. N/C 0
2. P/DIM4 Jumps
3. D-ON/OFF Jumps
4. P/DIM3 Jumps
5. GND
6. P/DIM2 Jumps
7. B13V Jumps
8. P/DIM1 Jumps
9. B13V Jumps
10. N.C. 0
11.VAMP Jumps
12. BLU ON/OFF Jumps
13. VAMP Jumps
14. GND
15. GND
16. GND
17. B5V Jumps
18. A5V Jumps between 5.27 and 5.26
19. B5V Jumps
20.PWR ON/OFF 0.87v jumps upto 2.3?v

All the ones I have wriiten just jumps beside, jump from 0

[dick_barton]

Re: Samsung UE40F6320AK on / off boot loop problems

If you disconnect the power supply from the main board and jumper A5V to PWR ON/OFF using a 1K resistor and switch on, does the B5V and B13 supplies come on.

[Bloopeta]

Re: Samsung UE40F6320AK on / off boot loop problems

If you disconnect the power supply from the main board and jumper A5V to PWR ON/OFF using a 1K resistor and switch on, does the B5V and B13 supplies come on.

Ill get a 1k resistor and try

[budm]

Re: Samsung UE40F6320AK on / off boot loop problems

"20.PWR ON/OFF 0.87v jumps upto 2.3?v"
So the PS-ON pin is jumping up and down between 0.87 and 2.3V?
BTW, PS-ON pin has built-in pull up SMD resistor R5852 to pull PS-ON pin high for power supply self test.

Samsung BN44-00622D
https://www.shopjimmy.com/samsung-bn...led-board.htm#

[Bloopeta]

Re: Samsung UE40F6320AK on / off boot loop problems

"20.PWR ON/OFF 0.87v jumps upto 2.3?v"
So the PS-ON pin is jumping up and down between 0.87 and 2.3V?
BTW, PS-ON pin has built-in pull up SMD resistor R5852 to pull PS-ON pin high for power supply self test.

Samsung BN44-00622D
https://www.shopjimmy.com/samsung-bn...led-board.htm#

Hi yes, it 0.87, then when clicks jumps up to 2.3something volts, then when clicks less than a second later goes back down to 0.87, then repeats in continuos loop

[budm]

Re: Samsung UE40F6320AK on / off boot loop problems

Are you 100% sure that the A5V is not jumping between <2 V and 5V?

[Bloopeta]

Re: Samsung UE40F6320AK on / off boot loop problems

Are you 100% sure that the A5V is not jumping between <2 V and 5V?

Hi, yes sure, unless im testing the wrong pin, ive attached pics and marked it in red.

[Bloopeta]

Re: Samsung UE40F6320AK on / off boot loop problems

If thats the correct pin, this is the reading

[dick_barton]

Re: Samsung UE40F6320AK on / off boot loop problems

The pin numbers are given alongside the socket.

[Bloopeta]

Re: Samsung UE40F6320AK on / off boot loop problems

The pin numbers are given alongside the socket.

Yeah I was just double checking incase I had the top and bottom mixed up lol, ive ordered 1k resistors to check what you suggested, ill update you with the results when they arrive.