Samsung PN60E550D1F no audio no image only red LED

[jose6326]

my friend asked me to look at his tv

he said that he would have to power it on and off several times to get it to work properly
then he couldnt get an image just sound
now that I have the set it has no image or sound just the red standby LED

when i power it on with the remote the red LED blinks 5 times and goes away

i notice the green LED blinking on the logic board

i read 2 posts on here that the main board or the ICE3BR0665J on the ymain may be suspect

i did the initial voltage testing that i learned on here thanks to many of you guys on this great site

VS 210v when powered on then drops to 10.45v
VA 56.9v when powered on and drops to 0.019v
VE 10.92v
VSC -0.014v

i tested connector 804 on the PSU

1. GND
2. 0.123v
3. 0.006v
4. 0.001v
5. gnd
6. -0.003v
7. 15.32v
8. gnd
9. 0.007v
10. 0.001v
11. 10.45v
12. 10.45v

connector 801 on PSU

1. 0.123v
2. 5.23v
3. gnd
4. 15.31v
5. gnd
6. gnd
7. 5.18v
8. 5.18v
9. gnd
10. 15.32v
11. 15.32v
12 5.18v


i will try disconnecting the ymain and see if anything changes

what else should i test?


thanks

[jose6326]

Re: Samsung PN60E550D1F no audio no image only red LED

Pics of the connectors

[tom66]

Re: Samsung PN60E550D1F no audio no image only red LED

Screen is free of cracks / damage?

[jose6326]

Re: Samsung PN60E550D1F no audio no image only red LED

no cracks no damage

[tom66]

Re: Samsung PN60E550D1F no audio no image only red LED

Check Vscan with buffer removed

[jose6326]

Re: Samsung PN60E550D1F no audio no image only red LED

Remove Both upper and lower y buffers?

[jose6326]

Re: Samsung PN60E550D1F no audio no image only red LED

I removed both buffers

Vscan is -63.4v
Vs is 210.9v
Va is 56.8v
Voltage readings are constant

[freakaftr8]

Re: Samsung PN60E550D1F no audio no image only red LED

Vscan is way to low.

[jose6326]

Re: Samsung PN60E550D1F no audio no image only red LED

Once I removed the buffers va and vs came back to normal. Im guessing one of the buffers are bad? Or something on the ymain?

[Hamie]

Re: Samsung PN60E550D1F no audio no image only red LED

You have a problem with your y-sustain.
Buffers might be ok, best to check the ICs for low resistance to ground.

[jose6326]

Re: Samsung PN60E550D1F no audio no image only red LED

which IC's?

thanks for the help

[jose6326]

Re: Samsung PN60E550D1F no audio no image only red LED

i read on another post that the IC and blue caps may be the cause

sorry for the poor pic quality

[tom66]

Re: Samsung PN60E550D1F no audio no image only red LED

Vscan should be closer to -200V
unless that is the HIGH scan voltage which may be 150V above -Vscan (approx -50V)
Try checking between floating ground and scan outputs of the buffer board, the floating ground is on the connector with many pins connected together, and the HIGH scan output has a few pins joined to each other (basically where you'd check on an older buffer board for a short)

[jose6326]

Re: Samsung PN60E550D1F no audio no image only red LED

I tested vscan where I markes it in the picture

Is that the correct test point?

[jose6326]

Re: Samsung PN60E550D1F no audio no image only red LED

I have a new ICE3BR0665J and I decided to test it on the ohms setting and compare it to the one on the ymain

The top 2 legs on the new IC read 0.1 ohms
The one on the ymain read OFL
Does this mean it is shorted?

[jose6326]

Re: Samsung PN60E550D1F no audio no image only red LED

Tom66 I seen you provided a youtube vid that shows how to test the buffer boards. I put the meter on ohms and put the negative lead on the ymain side connector and ran the positive lead across both sides of the solder points on the buffer side connectors.
I did not not get any beeping sounds
Im guessing the chips are not shorted

[tom66]

Re: Samsung PN60E550D1F no audio no image only red LED

Try checking between SVC YOUT and Vscan should read approx 150V

[jose6326]

Re: Samsung PN60E550D1F no audio no image only red LED

I get -46.8v when I place the leads on chassis ground and positive lead on the svc_yout test point

[jose6326]

Re: Samsung PN60E550D1F no audio no image only red LED

did i test this correctly?

[jose6326]

Re: Samsung PN60E550D1F no audio no image only red LED

So I replaced the ic chip with a new one and I replaced the 3 blue caps near the ic with some other exact blue caps from another board I had

I connected everything back powered it on and nothing
No image on the screen

I tested the voltages with logic board connected and same results vs and va dropped.
Vsc was at 0.002 with and without logic board connected

I removed the buffer boards and disconnected the logic board va and vs went back to spec but vsc went -63.4v

What else can I do