Element ELEFW40C won't turn on.

[Spork Schivago]

Re: Element ELEFW40C won't turn on.

This is the exact one i had ordered


http://www.ebay.co.uk/itm/CH341A-24-...vip=true&rt=nc

it does list the winbond W25Q16 ic if its the same ic as yours

The main issue is we dont know if your eeproms at fault and if it is you will need the correct firmware for the board that matches the panel etc to re programme the ic ive just looked on shopjimmy and cant see any boards for this tv?

I didn't look to hard, but I couldn't find a replacement board either. I ordered the one I linked too. The software and drivers should be compatible, I'd think. I've sent Stj a PM asking if he still had version 1.18 and version 1.29 of the software. I've also ordered an expensive can of that canned freeze stuff from a company called MG or something. Supposedly, it'll cool the chip down to -51F or something like that. I guess people have varying degrees of success freezing the bad chips and then reading them.

I'll remove it, try to read it, if it doesn't work, try to freeze it, if it doesn't work, I'll try to somehow verify the software is compatible with the chip I'm playing with. Then I'll try to find someone who dumped the firmware from it and buy a replacement chip, unless of course, I can successfully read it.

Any other ideas what to check while I'm waiting for delivery?

[vinceroger69]

Re: Element ELEFW40C won't turn on.

i havnt saw stj post in a while i have his version 1.18 in a zip file what he had sent me so can upload that if needed, version 1.29 is a trial version i think? so not sure if needs activating to do all functions etc i use servisol freeze spray and maplins own version both are good but expensive but worth having some good spray in stock. im sure that programmer will come in handy with other projects im sure stj mentioned problems using the clips that go onto the ic without removing it im sure he will post in this thread when he see it.
I would keep trying too find a schematic whilst your waiting for parts etc that way you can be sure the psu sections ok etc.

[Spork Schivago]

Re: Element ELEFW40C won't turn on.

I did contact the company, but have very little hope in them providing anything useful. I found one of their service manuals for another model television and it's extremely simple. All it includes is how to disassemble the television, how to remove the various boards, how to reinstall the various boards, and part numbers for ordering the various boards.

The clip I ordered is not to be used in-circuit. It just allows me to hook it up to the reader / writer without having to resolder it to the PCB that comes with the reader / writer, so I was okay with that.

I also heard people seem to have better luck with version 1.18 of the software than they do with the v1.29. I've heard v1.29 tends to misidentify the chip.

On a side note, I went back to testing some components. I found something that I think is a little strange. It's what I believe is a surface mount capacitor. I set my DMM to continuity and although I haven't removed the surface mount component, for some reason, when I test it, I get 0.000 ohm resistance. There are other components on the board that look like this, and none of them read the same way. I've uploaded a picture with a red block around the component I'm talking about.

Could this be causing issues?

[CapLeaker]

Re: Element ELEFW40C won't turn on.

if it is a surface mount capacitor and there is a short, I'd be checking that out. However it is an inductor, or a 0 ohm resistor a short is normal. I can't tell on that picture.

[Spork Schivago]

Re: Element ELEFW40C won't turn on.

if it is a surface mount capacitor and there is a short, I'd be checking that out. However it is an inductor, or a 0 ohm resistor a short is normal. I can't tell on that picture.

How would I be able to tell the difference? There's a silk screen layer but it's hard to tell what's what. Most of the devices on the top side seem to have labels on the bottom side. This makes it really hard to identify components. There's other SMD devices that look like this, but different sizes. They all show something that isn't 0 ohm resistance...in fact, I believe all of their resistances change, which I believe is normal, if they're capacitors, because they're charging up while I'm measuring them, right?

Are there any tests I can run? For example, press the ON button and attempt to carefully read voltage on both sides of it, to give us a better idea of whether it's a cap or an inductor?

[Spork Schivago]

Re: Element ELEFW40C won't turn on.

Current through a capacitor changes, but voltage doesn't, right? And voltage changes through an inductor, but current doesn't, right? So, shouldn't I be able to put my DMM, set to VDC, and see if the voltage is changing or not while I measure the voltage drop of the component in question?

[budm]

Re: Element ELEFW40C won't turn on.

Vf of the semiconductor varies little with the amount of current flowing through it, see graph of the spec sheet of the Diode.
Diode is not resistor, more current flow through resistor = more Vdrops on the resistor.

[Spork Schivago]

Re: Element ELEFW40C won't turn on.

Okay Budm. Thank you.

Any ideas how to tell if that one device is an SMD inductor or an SMD capacitor? Can you maybe tell by the surrounding components? Maybe you'll recognize the circuit and know if it's an inductor or a cap.

[budm]

Re: Element ELEFW40C won't turn on.

Okay Budm. Thank you.

Any ideas how to tell if that one device is an SMD inductor or an SMD capacitor? Can you maybe tell by the surrounding components? Maybe you'll recognize the circuit and know if it's an inductor or a cap.

Which parts are you talking about?
So what DCV do you have on the Cathode of that diode with ref to cold side circuit GND that you put the red rectangular marking in the picture?

[budm]

Re: Element ELEFW40C won't turn on.

How would I be able to tell the difference? There's a silk screen layer but it's hard to tell what's what. Most of the devices on the top side seem to have labels on the bottom side. This makes it really hard to identify components. There's other SMD devices that look like this, but different sizes. They all show something that isn't 0 ohm resistance...in fact, I believe all of their resistances change, which I believe is normal, if they're capacitors, because they're charging up while I'm measuring them, right?

Are there any tests I can run? For example, press the ON button and attempt to carefully read voltage on both sides of it, to give us a better idea of whether it's a cap or an inductor?

That looks like and inductor, you can trace the connection to see how the two legs are connected. Most of of the time the capacitor will have one leg connected to GND, inductor is usually connected in series with the load, that part is probably Ferrite bead inductor.

[Spork Schivago]

Re: Element ELEFW40C won't turn on.

Which parts are you talking about?
So what DCV do you have on the Cathode of that diode with ref to cold side circuit GND that you put the red rectangular marking in the picture?

There's now two pictures with red squares. The first red square is around the diode. I have 37.2VDC.

The 2nd picture with the red square ( https://www.badcaps.net/forum/attach...6&d=1486593073 )

That's the SMD component. When the power is unplugged from the TV, if I check the continuity, it measures 0.000 ohm. If that's an SMD capacitor, then I think I found a problem. But it might be an SMD inductor. It's in the same area as to where that diode is.


I just read your second message about how to test and I believe it's an inductor. There's a screw that has a grounding wire connected to it. I've been using that for my black probe and it works real well. I checked the continuity between that SMD component and the GND, both sides of that SMD component show resistance. That would mean it's definitely an inductor, right? Thanks for the tip on how to check!

[Spork Schivago]

Re: Element ELEFW40C won't turn on.

Budm, so I started probing around with the DMM set to volts DC on the hot side of the PSU. I found a big resistor that runs under a heatsink. I have my black probe set to a GND on the HOT side and my red probe set to the end of the resistor, it's reading 0VDC. The other big resistors read a lot more than 0VDC (some read around 197VDC). Could this indicate a problem? I think under that heatsink is mosfet.

[budm]

Re: Element ELEFW40C won't turn on.

Budm, so I started probing around with the DMM set to volts DC on the hot side of the PSU. I found a big resistor that runs under a heatsink. I have my black probe set to a GND on the HOT side and my red probe set to the end of the resistor, it's reading 0VDC. The other big resistors read a lot more than 0VDC (some read around 197VDC). Could this indicate a problem? I think under that heatsink is mosfet.

You are using the chassis GND as the GND ref for you probe, right? I can tell by the DCV you are indicating. What is the exact GND in the hot side you are using?
Just remember one thing about this power supply board, it only has ONE power transformer! It is an ALWAYS on power supply so there will be some DC output Voltage present which you have so it means the PRIMARY side is working, some of the DC output are fed into switched MOSFET that is tyrned on when TV is turned on. So no need to look at the primary side, the drive circuit in the primary is running.
This board is not easy to trouble shoot due to density and it is also double-sided board so it is really hard for me to trace out the circuits in details. Since this board is power supply/LED driver/main board all in one so you will not have the typical connector with PS-ON pin. Right now we do not know if we have PS-ON, BL-ON or not.
BTW, that resistor under the Black heatsink in the primary side looks to be the resistor for he SOURCE pin of the POWER MOSFET that drives the power transformer primary winding. One side of that resistor is connected to the primary circuit GND ref.

[Spork Schivago]

Re: Element ELEFW40C won't turn on.

For the GND on the hot side, I am using the screw on the heatsink that goes to what I think is the MOSFET. For the cold side, I'm using the chassis GND. There's a screw that I have connecting to the chassis and black wire connectors to that screw. I put the probe on that screw when I test the cold side. I put the black probe on the screw on the heatsink when I check the hotside.

Do you want me to try and take more pictures, but not zoomed in? I can try to take pictures of the whole board or I can try and take some zoomed in pictures but splice them together to make one big zoomed in picture of the entire board.

I gotta go to bed now though because I gotta get up early with my daughter. She likes to wake up anywhere between 4:00AM and 6:30AM. I like to try and wake up before her, so I can get some coffee in me and not get woke up to her crying.

Thanks for helping though. I appreciate you sharing your knowledge with me, along with everyone sharing their knowledge as well. Thanks guys!

[budm]

Re: Element ELEFW40C won't turn on.

For the GND on the hot side, I am using the screw on the heatsink that goes to what I think is the MOSFET. For the cold side, I'm using the chassis GND. There's a screw that I have connecting to the chassis and black wire connectors to that screw. I put the probe on that screw when I test the cold side. I put the black probe on the screw on the heatsink when I check the hotside.

Do you want me to try and take more pictures, but not zoomed in? I can try to take pictures of the whole board or I can try and take some zoomed in pictures but splice them together to make one big zoomed in picture of the entire board.

I gotta go to bed now though because I gotta get up early with my daughter. She likes to wake up anywhere between 4:00AM and 6:30AM. I like to try and wake up before her, so I can get some coffee in me and not get woke up to her crying.

Thanks for helping though. I appreciate you sharing your knowledge with me, along with everyone sharing their knowledge as well. Thanks guys!

Unless that heatsink is connected to the negative leg of the main filter cap, then it is not GND ref, GND ref for the primary circuit is the negative leg of the main filter cap. Most heatsinks in the primary side are not connected to the primary GND.

[Spork Schivago]

Re: Element ELEFW40C won't turn on.

Is the main filter cap that 400V 120uF capacitor? Tomorrow, I'll try to make one big picture for each side of the board, maybe things will be easier to see then.

I found some pads that looked interesting though. One that says something like 1.35_STDBY, one that says something like RV5. There's one that says 3.3V but on the other side of the board, there's a header there and it says something about PWR_UPGRADE so I don't think that's to check if 3.3V is there. Anyway, just thought maybe those could come in useful for testing purposes.

[budm]

Re: Element ELEFW40C won't turn on.

No need to do any probing in the primary side. We need to find out where the command pins/traces are to see if they are present or not in the cold side.

[budm]

Re: Element ELEFW40C won't turn on.

Can you please do the super clear hi-res straight shot of top and bottom side of the WHOLE board?

[budm]

Re: Element ELEFW40C won't turn on.

What are the DCV between chassis and the Cathode 1, 2, 3, and 4?
What is the DCV MEASURED BETWEEN THE TWO LEGS OF THAT MARKED CAP?
Also need the Voltage rating of that cap.

[Spork Schivago]

Re: Element ELEFW40C won't turn on.

Can you please do the super clear hi-res straight shot of top and bottom side of the WHOLE board?

I will try to do that today. I have a tripod, but on the view screen of the camcorder, it looks sooooo small, but I noticed when I transfer them over to the PC, they're a heck of a lot larger than I expect. This is a small board, so maybe just one normal picture will show us everything (one of each side). I'll play around and see what we can get.

Is the main filter cap that 400V 120uF cap?