Philips 32pfl3403d/27 no power

[budm]

Re: Philips 32pfl3403d/27 no power

BTW you were testing the resistance between the AC inlet male pins and the bridge rectifier but not the all the way to the AC plug male pins, is that correct?

[Georgia088]

Re: Philips 32pfl3403d/27 no power

I placed one probe on the male pin that sticks up on the board that makes a connection with the power chord female end when the chord is plugged in. The other probe on either pin 2 or 3. I hope I'm not being confusing as I am trying not to be. And I do appreciate your patience and help.
Thanks.

Another stupid question

Is .004 not enough resistance to mean something is open between the 2n male pin and the bridge?

[budm]

Re: Philips 32pfl3403d/27 no power

You need to check between the AC male plug that goes into the Wall AC outlet all the way to the two inner pins of the Bridge.

[Georgia088]

Re: Philips 32pfl3403d/27 no power

So plug the power chord in and then check the resistance from the ac inlet to the bridge?

[budm]

Re: Philips 32pfl3403d/27 no power

1) The AC Inlet is on the circuit board.
2) You will plug the Female end of the Power cord into that AC Inlet.
3) You will check the resistance between the AC Power cord male pins and the two inner pins of the bridge rectifier.

[Georgia088]

Re: Philips 32pfl3403d/27 no power

Ok. I followed exactly what you said:
L1 to pin 3 shows 0.000 resistance on 200 setting of multimeter.

N2 shows 5.04-5.05 on same ohm setting.

Does this mean open circuit?

[R_J]

Re: Philips 32pfl3403d/27 no power

You will measure (aprox) 2.5 ohms (TH901 is a inrush thermistor) between N2 and pin 2 of the bridge rectifier
You will measure (aprox) 0 ohms between L1 and pin 3 of the bridge rectifier

[budm]

Re: Philips 32pfl3403d/27 no power

I think you have Hot and Neutral reverse in you thinking (unless they put the Thermistor on the Neutral which is not common).
I expect seeing that 5 Ohms resistance between the HOT PIN OF THE AC plug to one of the two inner legs of the bridge, that is due to that Green disc Thermistor right next to the AC inlet. The Neutral to the bridge will be <1 Ohm.
So the bottom line is that it does not have open circuit, with that low resistance between the bridge and the power cord male pins I cannot see why you do have 120 VAC between the two legs of the Bridge rectifier.
It is time for us to see the straight shot pictures of the top and bottom side of that power supply board, there must be error in measurement some where.

[R_J]

Re: Philips 32pfl3403d/27 no power

If you remove the power supply from the tv and turn it over to expose the circuit traces. It should look like the picture
Place the board upside down on an insulated surface (use cardboard or a book)
Plug the power supply in and check for 120 volts at the ac inlet.
If you have 120 volts ac at the inlet then move your probes to the next spot where it says c908.
If you have 120 ac there, move your probes to where it says c909
If you have 120 volts ac there then check at the bridge
at any point you do not have 120 volts ac, your fault is between that point and the previous test point

Note: when you are checking be carefull and make sure the probes contact solder points and not the actual trace as the traces are usually covered with a green paint and you may not get a proper reading.

[Georgia088]

Re: Philips 32pfl3403d/27 no power

So when testing for 120v at each point, should I place one probe on one pin and one probe on other pin of each individual component? Or, should I place black probe on a known ground and check each pin with red probe to see if it has 120v?

[R_J]

Re: Philips 32pfl3403d/27 no power

Put the probes like I marked them on the picture, (see the RED and BLACK looking probes It does'nt matter if the red and black are reversed, your measuring ac volts

[Georgia088]

Re: Philips 32pfl3403d/27 no power

So again I think I've made a stupid mistake and I apologize. I did not have much time this morning to check, but when I made my first test based on the drawing I did not get 120 v. This made no sense bc I could get 120v the other day. So I started checking again. I can get 120v to several places as long as I touched a grounded screw with the board on the chasis but when testing across l1 and n2. Nothing.

So, I tested chord. I could get 120v at chord when placing probes in l1 plug and the middle plug. However, I could not get it when placing the probes in two outside female parts of power chord.

This is not the power cable that came with the tv. So, I do not believe this is was my original problem, but I do think it has completely skewed any testing results I have given. I completely apologize!

I will put another power chord on tv and begin testing procedure again. I will be posting results soon. Thanks again!!!

[budm]

Re: Philips 32pfl3403d/27 no power

You are testing incoming AC so you will test the AC Voltage between HOT and Neutral not to the middle prong which is safety GND.
As long as the circuit see the incoming AC between HOT and Neutral that is all it cares, SAFETY GND is in case is for fault current, TV does not need safety gnd to operate.
"So, I tested chord. I could get 120v at chord when placing probes in l1 plug and the middle plug. However, I could not get it when placing the probes in two outside female parts of power chord. '
How can that be when you reported the resistance reading as I requested as 0 Ohm on one leg to the rectifier and about 5 Ohms on another leg to the rectifier with that so called wrong power cord?
This whole DATA we are receiving seems to be full of errors, I wonder if we can trust what you are reporting.
BTW, the Middle prong of the AC male plug is safety GND.

[Georgia088]

Re: Philips 32pfl3403d/27 no power

Again, I apologize for being stupid. I can't explain the results I am getting. Would The resistance between the n2 and the pin on the rectifier be affected if the break in the line was on the power chord side? Another words, I am apparently not getting continuity from the electrical outlet to the point that the chord is plugging in to the board. The reading I gave you was from the board to the bridge rectifier. Would this change if the power chord was bad?

Thanks again

[R_J]

Re: Philips 32pfl3403d/27 no power

My money is on a bad power cord or broken connections on the inlet to the board

[budm]

Re: Philips 32pfl3403d/27 no power

My post 45:
1) The AC Inlet is on the circuit board.
2) You will plug the Female end of the Power cord into that AC Inlet.
3) You will check the resistance between the AC Power cord male pins and the two inner pins of the bridge rectifier.

So now you are telling me that you did not test as I requested in post 45?
Post 46:
Ok. I followed exactly what you said:
L1 to pin 3 shows 0.000 resistance on 200 setting of multimeter.

N2 shows 5.04-5.05 on same ohm setting.

Does this mean open circuit?
And now this post 54?
Again, I apologize for being stupid. I can't explain the results I am getting. Would The resistance between the n2 and the pin on the rectifier be affected if the break in the line was on the power chord side? Another words, I am apparently not getting continuity from the electrical outlet to the point that the chord is plugging in to the board. The reading I gave you was from the board to the bridge rectifier. Would this change if the power chord was bad?
Thanks again

We are up to 56 posts now.
All you have to do is to follow the instructions.

[Georgia088]

Re: Philips 32pfl3403d/27 no power

You are right! I did not test the way you said. I read again and understand what you are saying. I should not have the power chord plugged in when I did the test. I tested from the board with the power chord plugged in. I didn't read your instructions carefully enough apparently! I am sorry.

I will get another power chord and test again!

Thanks!!

[Georgia088]

Re: Philips 32pfl3403d/27 no power

Ok. New power supply chord still no tv.

However, with new power supply chord:

I get 120v out of middle pins of rectifier

I get 169 vdc out of big black capacitor

I get 5v at both 5v pins of connector that goes to main board: ( this is with one probe on grnd in connector and other on 5v pins)

I do not get any voltage at any of other pins including standby when tested the same way

I get nothing from other connector that goes to inverter board:

All of this was tested with power supply disconnected from all other boards if this matters.

Thanks again for the help!!

[dskall]

Re: Philips 32pfl3403d/27 no power

Plug everything back in and see if it works.

[Georgia088]

Re: Philips 32pfl3403d/27 no power

I plugged it all back in and still nothing.