RCA no power indicator

[Minkota]

I have an RCA LED50B45RQ television that will not turn on. I am unsure what happened we came home one night and it just would not turn on.
On the bottom left corner there is a little LED that normally turns blue when the unit is on, but right now when I plug the unit in the light will come on as "Red" and then slowly dim until it goes out. Does this sound like the Power Board went bad? I opened it up thinking there might be a fuse, but I do not see one anywhere. Can anyone tell me the best way to determine the problem?

[budm]

Re: RCA no power indicator

Do you have meter for checking the Voltage? You need to have that at least.

[Minkota]

Re: RCA no power indicator

Do you have meter for checking the Voltage? You need to have that at least.

Yes, I do.

[budm]

Re: RCA no power indicator

https://www.badcaps.net/forum/attach...0&d=1501269880
The top left connector that goes to the main board should have pin lable for each pin, it may be on the top or on the bottom side of the board, we will need to find out what the DCV are for those pins.

[Minkota]

Re: RCA no power indicator

https://www.badcaps.net/forum/attach...0&d=1501269880
The top left connector that goes to the main board should have pin lable for each pin, it may be on the top or on the bottom side of the board, we will need to find out what the DCV are for those pins.

I checked the board as directed, there is 0(zero) voltage at every terminal.

[budm]

Re: RCA no power indicator

Well, if you did see the light comes up red as in pots 1, then there must be Voltage present at 5VSB (5V Standby Power). If you run just the power supply board by itself without other boards connected to it but still have 120VAC feeding the board, do you see Voltage at the 5VSB at all?

[Minkota]

Re: RCA no power indicator

I just checked again with the board Connected and disconnected to the main board and I am getting 10v at the 12v terminals and 3 volts at the other non-ground terminals.
I am not sure why i was not getting a reading before.

[Minkota]

Re: RCA no power indicator

double post

[budm]

Re: RCA no power indicator

How about the 5VSB? That 5V should be present the minute you apply 120VAC to the power supply board, it is an always on power supply, most other Voltage are switched which is turned on when PS-ON signal from main board is present.

[Minkota]

Re: RCA no power indicator

How about the 5VSB? That 5V should be present the minute you apply 120VAC to the power supply board, it is an always on power supply, most other Voltage are switched which is turned on when PS-ON signal from main board is present.

it is showing 3 volts

[Minkota]

Re: RCA no power indicator

is the voltage readings I am getting indicative of a bad "Power Board"?

[budm]

Re: RCA no power indicator

If you run the power supply board by itself and the STANDBY 5V is only showing 3V then you have at least with the standby power supply section.

[Minkota]

Re: RCA no power indicator

If you run the power supply board by itself and the STANDBY 5V is only showing 3V then you have at least with the standby power supply section.

I am not sure I understand what your telling me to do. Can you please explain?

[dskall]

Re: RCA no power indicator

Unplug mainboard connector and check voltage

[Minkota]

Re: RCA no power indicator

Unplug mainboard connector and check voltage

I did that and the voltages stay the same.

[budm]

Re: RCA no power indicator

I did that and the voltages stay the same.

So you are getting only 3V without the main board connected, so unplug the AC cord from the wall then try heating up capacitors EC2, EC3, EC14 in that Standby power supply section with hair dryer for about 2 minutes then plug the AC cord back into the outlet and then check to see if you will get the 5V from Standby supply or not.
BTW, did you verify that your meter DCV is OK or not? The reason I ask because the 12V is generated by other power supply circuit and it is also showing 10V instead of 12V.

[Minkota]

Re: RCA no power indicator

So you are getting only 3V without the main board connected, so unplug the AC cord from the wall then try heating up capacitors EC2, EC3, EC14 in that Standby power supply section with hair dryer for about 2 minutes then plug the AC cord back into the outlet and then check to see if you will get the 5V from Standby supply or not.
BTW, did you verify that your meter DCV is OK or not? The reason I ask because the 12V is generated by other power supply circuit and it is also showing 10V instead of 12V.

After doing that I still get the same voltage readings...

[dskall]

Re: RCA no power indicator

You might try reading a 1.5v, 9v battery to confirm accuracy of your meter

[Minkota]

Re: RCA no power indicator

I am assuming the discerpency in voltage is on the meter not the television since it is showing 2v low for everything I have tested with it.

Does the mean the main board need replacing?

[budm]

Re: RCA no power indicator

You need to use good working meter to really verify the Data.