Samsung LN46D630M3FXZA blinking stby LED

[steves7839]

This TV has no sound or picture. When turned on, the TV standby LED blinks three or four times repeatedly a few times, then stays off. The backlight comes on when the Power Supply-Main Board cable is left unplugged. Neither Power Supply or Main Board show any visibly damaged components. Leaving the LVDS cable disconnected makes no difference.

I have replaced the main board twice with used parts, once with a substitute and once with the same part number. Symptoms stay the same.

I am posting photos of voltage readings at the PS/MB connector. After two unsuccessful Main Board replacements I'm not sure the PS is working.

Voltages with CN201 disconnected is at the top of the fourth photo. Differences when CN201 is connected to the Main Board are noted below.

Second opinions please?

[CapLeaker]

Re: Samsung LN46D630M3FXZA blinking stby LED

No one is going to understand that what's written on the TV. Put your reading together with a pinout name and post it here.

While you are at it, unplug the main board from the PSU, then plug the PSU in so the backlights come on and measure the pinouts again and post the outcome.

[steves7839]

Re: Samsung LN46D630M3FXZA blinking stby LED

Here they are:



CN201 connected:
Pin Signal Reading Connected: Reading CN201 unplugged if diff:

1,3 B18VS 12.0V 12.6V
5,6,7 B5V 3.8V 4.8V
8-11 GND 0V
12 HSYNC 0V
13,15,17 B13V 12.6V
14 PWM_DIM 4.6V
16 SW_INV 4.8V
18 N/C
4 A5V (STBY) 5.2V

[CapLeaker]

Re: Samsung LN46D630M3FXZA blinking stby LED

Could you post a high resolution, straight shot picture of your PSU front and back, please?

Only thing I can see is something doesn't rhyme up on pin 1 and 3. Label sez 18V and you get 12V? But then the backlight shouldn't be working either when the main board is unplugged... weird.

[steves7839]

Re: Samsung LN46D630M3FXZA blinking stby LED

On the PSB those pins are referenced 13/18VS. The backlight receives power thru a different connector, CN1802. I have downloaded the quickstart service manual for the tv. It shows 13V on that pin.

Attaching board photos of the Power Supply BN44-00463A.

[budm]

Re: Samsung LN46D630M3FXZA blinking stby LED

Here they are:



CN201 connected:
Pin Signal Reading Connected: Reading CN201 unplugged if diff:

1,3 B18VS 12.0V 12.6V
5,6,7 B5V 3.8V 4.8V
8-11 GND 0V
12 HSYNC 0V
13,15,17 B13V 12.6V
14 PWM_DIM 4.6V
16 SW_INV 4.8V
18 N/C
4 A5V (STBY) 5.2V

I do not see pin 2 SW_PWR (PS-ON), it is probably present otherwise you will not have the switched supplies outputs.
Pin 5, 6, 7 B5V (switched 5V) is only 3.8V when connected is also not right.
The B13V (Switched 13V) is not tightly regulated so reading of 12.6V is fine.

[budm]

Re: Samsung LN46D630M3FXZA blinking stby LED

BN44-00463A
http://www.shopjimmy.com/samsung-bn4...upply-unit.htm

Pictures provided by shopjimmy.

[Landcaster3]

Re: Samsung LN46D630M3FXZA blinking stby LED

I have the same problem on my UN40H635AFXZA TV. When I disconnect the connector to the main board I get two results the backlight turns on and the voltages go from reading low to normal...I suspect I have a bad power supply.

[dick_barton]

Re: Samsung LN46D630M3FXZA blinking stby LED

What PS_ON and SW_INV voltage do you have when mainboard connected and coming out of standby?

[CapLeaker]

Re: Samsung LN46D630M3FXZA blinking stby LED

either something is drawing a lot of current on the 5v rail or the 5v filter cap is bad.

[steves7839]

Re: Samsung LN46D630M3FXZA blinking stby LED

What PS_ON and SW_INV voltage do you have when mainboard connected and coming out of standby?

SW_PWR is 3.1VDC
BLU_ON is 4.8VDC

To answer BudM's comment, yes, P5A (standby) is present and 5.2VDC.

[budm]

Re: Samsung LN46D630M3FXZA blinking stby LED

I am talking about B5V.
'5,6,7 B5V 3.8V 4.8V' That is bad, you are getting 3.8VDC.