Proscan 50" PLDED5066A-E no backlights

[mnpdreed]

Re: Proscan 50" PLDED5066A-E no backlights

1 (GND)
2 (GND)
3 (+5V) =5.02v
4 (+5V) =5.02v
5 (PS-ON) =4.42v
6 (+5VSB) =5.04v
7 (+5) =5.02v
8 (+5) =5.02v
9 (GND)
10 (GND)
11 (GND)
12 (+12V) =11.90v
13 (+12V) =11.90v

[budm]

Re: Proscan 50" PLDED5066A-E no backlights

OK, I found pictures of the board AY128D-4SF51 which looks really close to your board AY128D-4SF11.
As you can see, CON3 has the pin labels on the bottom side of the board, so I need to know what the Voltages are (yo post the Voltage readings but did not assign pin numbers or the pin name with the readings).
I need to find out if you do have >2.5VDC on pin 5 (PS-ON) or not, and the Voltage readings of the rest of the pins.
Pictures provided by SHOPJIMMY.
1 (GND)
2 (GND)
3 (+5V) =
4 (+5V) =
5 (PS-ON) =
6 (+5VSB) =
7 (+5) =
8 (+5) =
9 (GND)
10 (GND)
11 (GND)
12 (+12V) =
13 (+12V) =

[budm]

Re: Proscan 50" PLDED5066A-E no backlights

https://www.badcaps.net/forum/attach...9&d=1448074584
This one is cut off on the top, I am trying to see how the small green daughter board pins are connected to the main power supply board.

[budm]

Re: Proscan 50" PLDED5066A-E no backlights

I don't know if you saw this pic of the voltage readings and don't know if this means anything but it has voltage going into L2 but nothing coming out

I need to trace out the circuits, so I am looking at the closed up pictures I requested to get some ideas how it works.

[mnpdreed]

Re: Proscan 50" PLDED5066A-E no backlights

I don't know if you saw this pic of the voltage readings and don't know if this means anything but it has voltage going into L2 but nothing coming out

[mnpdreed]

Re: Proscan 50" PLDED5066A-E no backlights

Thank you for the help

[mnpdreed]

Re: Proscan 50" PLDED5066A-E no backlights

Pic

[budm]

Re: Proscan 50" PLDED5066A-E no backlights

OK, I need clear straight shot pictures of the two sections I mark, you will need to remove that white plastic plastic so I can see the traces.

[mnpdreed]

Re: Proscan 50" PLDED5066A-E no backlights

I check all of the board and nothing is brown or brownish under a magnifying glass

[mnpdreed]

Re: Proscan 50" PLDED5066A-E no backlights

Close up

[mnpdreed]

Re: Proscan 50" PLDED5066A-E no backlights

The two white pieces are plastic tabs that hold the clear plastic over the back. I can take take closes up of different sections of the board if that will help.

[CapLeaker]

Re: Proscan 50" PLDED5066A-E no backlights

Second pic top left corner, seems to be some SMD components that have a different brownish colour? Can't read it, as the pic is a bit blurry. Is that white round sticker for decoration?

[mnpdreed]

Re: Proscan 50" PLDED5066A-E no backlights

Thanks for helping. Here is the pics

[budm]

Re: Proscan 50" PLDED5066A-E no backlights

Can you take really good clear straight shot pictures of the whole top side and the bottom side of the power supply-LED driver board?

[mnpdreed]

Re: Proscan 50" PLDED5066A-E no backlights

Meter is set on DC. When CON1 is unplugged 011.1 mV then peaked at 2.06v drops to .639v DC. It is like no voltage is coming from or going to T2F with or without con 1 connected.

[CapLeaker]

Re: Proscan 50" PLDED5066A-E no backlights

When powered on with leads on con1volts start at -011.4 mv peak at 1.880 V then drop to .639v. The earlier post has the first reading as .639 mv and it should have read .639 Volts

are these voltages measured in DC? The voltages are low, almost like you had the DMM set to AC, that low. What happens when you disconnect the LED backlight and measure con1?
con1 has 5 pairs of LED's. You can test them separately, with variable bench power supply, however with the LED's being behind the diffuser, a bad LED can be easily missed.

I am looking for a very quick ramp up in power on con1. To rule out the backlight, you may have to take it apart.

[mnpdreed]

Re: Proscan 50" PLDED5066A-E no backlights

Any suggestion on what to do next. Thanks for the help.

[mnpdreed]

Re: Proscan 50" PLDED5066A-E no backlights

Is there a way to test the LED strips without taking the panel off. If so how. Thanks again for all the help.

[mnpdreed]

Re: Proscan 50" PLDED5066A-E no backlights

When powered on with leads on con1volts start at -011.4 mv peak at 1.880 V then drop to .639v. The earlier post has the first reading as .639 mv and it should have read .639 Volts

[mnpdreed]

Re: Proscan 50" PLDED5066A-E no backlights

All 4 diodes (MUR 460) in circuit tested .410 and OL in diode mode with DMM. Resistor are 10 ohms tested 5.3 in circuit