Sceptre X405BV-FHD3HF02205 no power

[dick_barton]

Re: Sceptre X405BV-FHD3HF02205 no power

Thanks budm for the correct pictures.

[budm]

Re: Sceptre X405BV-FHD3HF02205 no power

http://www.shopjimmy.com/sceptre-kw-...t-inverter.htm

Sceptre KW-PIV400102A Power Supply / Backlight Inverter.
Pictures provided by shopjimmy

[dick_barton]

Re: Sceptre X405BV-FHD3HF02205 no power

Dick, I don't see a board in my TV that looks like the one in your photo. If I'm missing something, please advise.
Paul

Sorry if it's the wrong board. What are the voltages on Connector 4?

[budm]

Re: Sceptre X405BV-FHD3HF02205 no power

So the BL-ON (Backlights ON) is not present, that is from the main board, other Voltages and signals are fine.

[plbrand]

Re: Sceptre X405BV-FHD3HF02205 no power

My apologies, I didn't understand precisely what you were looking for. Hopefully the attached document provides the necessary info.

Dick, I don't see a board in my TV that looks like the one in your photo. If I'm missing something, please advise.

The TV failed progressively. Initially, if I unplugged it, waited a few minutes and tried again, it would sometimes come on and operate normally for as long as it remained on. The frequency of coming on after this re-boot increased quickly until it won't come on at all - just the red standby light.

Because of the progressive nature of the failure, it would seem unlikely for a lightning strike, but may be a possibility.

Again, thank all of you for your patience and help.

Paul

[budm]

Re: Sceptre X405BV-FHD3HF02205 no power

Where are the names and pin number of the pins for CON4? You are not making it easy for us to help without putting the names of each pin.
GND
PS-ON
ADJ
BL-ON
+12V

[vinceroger69]

Re: Sceptre X405BV-FHD3HF02205 no power

Do you know the background of the tv as budm says it looks like the ps.on signal is always on which comes from the mainboard could this tv took a lightening strike? which may of damaged the mainboard just a thought.

is there anyway too test just the psu to rule it out by jumping pins? at least it will confirm a mainboard fault.

[dick_barton]

Re: Sceptre X405BV-FHD3HF02205 no power

Hello Paul,
There are several other connectors to be identified that would help to solve your problem if the voltages were known. I've marked them in red boxes.

[plbrand]

Re: Sceptre X405BV-FHD3HF02205 no power

Okay, I added the box printed on the PS board with the expected values in the individual boxes and my readings below. Hope this helps.

Paul

[vinceroger69]

Re: Sceptre X405BV-FHD3HF02205 no power

just by the connectors there a oblong box with what readings that connector should have and what each pin does can you add these too your word document so we can see what the voltages and pins should read etc.

edit just saw you can read them in picture 5 but if you can add them too it may help thanks

[plbrand]

Re: Sceptre X405BV-FHD3HF02205 no power

Okay, attached are connector pin voltages to ground for Conn 4, 3, 2 on the corner of the power supply board. The orientation is such that the edge of the board is toward the top.

Hope this helps!

Paul

[dick_barton]

Re: Sceptre X405BV-FHD3HF02205 no power

Meter black lead to chassis. Push red lead probe into top of the connector to measure. Or use a thin piece of wire attached to the red probe to push into the top of the connector. Meter set to DV volts. Connectors have Pin1, 2,3, etc.
So if you could tablulate the results something like:-

CON4
Pin Legend Reading

Pin 1 (GND) = 0V
PIn 2 (+5V) = ??
Pin 3 (+12V) = ??
etc

[plbrand]

Re: Sceptre X405BV-FHD3HF02205 no power

That will have to wait 'til tomorrow. How should I measure these voltages?

[dick_barton]

Re: Sceptre X405BV-FHD3HF02205 no power

What voltages do you have on Con2 & Con4 when you power up?

[plbrand]

Re: Sceptre X405BV-FHD3HF02205 no power

Well, I found time this afternoon, so here are the photos of the PS Board Top/Bottom, connectors, other boards and entire back of TV. I hope they are adequate, please let me know if you need more.

Thanks again,

Paul

[plbrand]

Re: Sceptre X405BV-FHD3HF02205 no power

Thanks very much for the prompt response. I won't be able to take the photos until tomorrow, but will post them as soon as I can.

Again, thank you for your help.

Paul

[budm]

Re: Sceptre X405BV-FHD3HF02205 no power

Hey guys, I have this exact Sceptre X405BV-FHD3HF02205 TV with the exact same boards. In my case, the red standby light comes on when the unit is plugged in, but nothing else. No picture, no sound, no blue light. The standby light does not change when the remote or the side panel power button are pushed. The diodes, including D10 seem good as they read normal with my DMM and none are shorted. A careful study of the caps doesn't show any obviously failed caps. I unplugged and replugged every connector on all the boards - but no joy.

Also, I checked the fuse on the power supply board - it's good. But I don't get the 165VDC across the legs of the big cap C51. On the 600VDC scale, it reads 385, which I don't understand. On the 200VDC scale, it reads 198 momentarily, then nothing.

I'm new to badcaps and appreciate the help you offer us amateurs. Thank you, Paul

it is showing 385VDC between the two legs of the main filter cap which means that the power supply board is getting the PS-ON from the main board. That Voltage should be at 160vdc when the TV is turned off, but if the main board is bad and has stuck ON PS-ON signal so the power supply will stay on and does not go off.
We need good clear pictures of YOUR whole backside of the TV that shows all the board, and then the pictures of the whole power supply board top side and bottom side of the board, closed up pictures of the connectors of the power supply board so we can read the pin labels.

[plbrand]

Re: Sceptre X405BV-FHD3HF02205 no power

Hey guys, I have this exact Sceptre X405BV-FHD3HF02205 TV with the exact same boards. In my case, the red standby light comes on when the unit is plugged in, but nothing else. No picture, no sound, no blue light. The standby light does not change when the remote or the side panel power button are pushed. The diodes, including D10 seem good as they read normal with my DMM and none are shorted. A careful study of the caps doesn't show any obviously failed caps. I unplugged and replugged every connector on all the boards - but no joy.

Also, I checked the fuse on the power supply board - it's good. But I don't get the 165VDC across the legs of the big cap C51. On the 600VDC scale, it reads 385, which I don't understand. On the 200VDC scale, it reads 198 momentarily, then nothing.

I'm new to badcaps and appreciate the help you offer us amateurs. Thank you, Paul

[dnixon]

Re: Sceptre X405BV-FHD3HF02205 no power

Finally got a new diode. Took almost 2 weeks. Out of stock plus delivery time. Anyway, got it replaced and TV works! Thanks to budm and vinceroger69 for all the help.

[budm]

Re: Sceptre X405BV-FHD3HF02205 no power

Thanks for the follow-up on the repair, glad that it was a simple repair.