Sony Bravia KDL-40W4100 wont turn on. Error code red LED blinks 3 times.

[lookimback]

Got this one earlier tonight. Thought I was gonna fix 3 in one day but no such luck. All I'm getting is a relay click then it shuts down. Backlights never come on. Red LED blinks 3 times. This, according to the service manual, means DC Alert 1. Exactly what that means? I have no clue. I've uploaded pics of the power board, top and bottom. Not sure it is the power board though. Hoping someone else has had similar problem and can point me in the right direction. All the diodes on power board are OK. Caps look OK but will test tomorrow. I'll post pics of the other boards tomorrow if needed. For now I'm calling it a night.

[kenny1070]

Re: Sony Bravia KDL-40W4100 wont turn on. Error code red LED blinks 3 times.

I'm currently working on a KDL-32s20L1 with the exact same problem.
On mine:
DC Alert 1 = Abnormal Panel Voltage
Stand-by 3.3v is the main supply for triggering this alert.
Hoping for a quick fix - I took a shot at swapping both the Inverter (common) and then the Power Supply - No Luck.
Today I'll start pinpoint testing - starting on the Stand-by line.

I hope that this somehow helps you.

Please let us know what you find.

[lookimback]

Re: Sony Bravia KDL-40W4100 wont turn on. Error code red LED blinks 3 times.

I'll start testing when I get home from work tonight. Thanks for the input. So you said you swapped out the power board and the inverter board? Then it must be something with the main board I'd think.

Edit: I'll tell you this much Kenny, you've come to the right place for help. There's a lot of very knowledgeable people here. Just please, if you figure it out, let us know. Thanks.

[kenny1070]

Re: Sony Bravia KDL-40W4100 wont turn on. Error code red LED blinks 3 times.

So I finally found it - Transfer chip/Regulator (lC7001) in the BU Board.

It took me a while, but the KDL-32s20L1 uses a secondary power supply (Protection line) in the BU Board that will draw the Stand-by 3.3vdc to ground - when it sees an output voltage irregularity (grounding switch).
The regulator chip failed - resulting in the lack of enough voltage to hold the grounding switch open. The end result is that the 3.3dcv was running to ground Before it could make it to the Microprocessor - Triggering the DC Alert-1.
Since I have neither the tools or ability to do this kind of micro-surgery, I'll look into a replacement board - if it's even possible (Protected/Locked) ???

Not sure how this may help you - but I certainly hope it does.
P.S. Bud M. has a full training manual of your model - posted on pg.2 of the first sticky (ctv-45 exidirectlcd.pdf).

[lookimback]

Re: Sony Bravia KDL-40W4100 wont turn on. Error code red LED blinks 3 times.

Could you post a pic so I can see what it looks like? I may have the same problem.

[budm]

Re: Sony Bravia KDL-40W4100 wont turn on. Error code red LED blinks 3 times.

Service manual:

[lookimback]

Re: Sony Bravia KDL-40W4100 wont turn on. Error code red LED blinks 3 times.

Thanks Bud. I had downloaded that from the site earlier. I was going to post it myself later. I have trouble getting things to upload sometimes. Not sure why. Usually I have to upload them to my site then upload them to badcaps from that URL. Otherwise it will just hang on the upload page. Does it from my phone and also my broadband connection.

[kenny1070]

Re: Sony Bravia KDL-40W4100 wont turn on. Error code red LED blinks 3 times.

I'm still trying to figure out how to do the posting/copy/upload thing here.
Unsuccessfully I might add.
But I'll help where I can.

Download ctv-45exidirectlcd.pdf (BUD M)
From page 2 of the first sticky -
Scroll to page 60 - DC Alert 1 trackline -check pin 11 at cn1411 for 12vdc.
If unsure of physical location - look at page 66 for a complete picture.

[lookimback]

Re: Sony Bravia KDL-40W4100 wont turn on. Error code red LED blinks 3 times.

Thank you. When I get home tonight I'll look into it and post back.

[budm]

Re: Sony Bravia KDL-40W4100 wont turn on. Error code red LED blinks 3 times.

Here is the training manual :https://www.badcaps.net/forum/showth...t=25810&page=2

[lookimback]

Re: Sony Bravia KDL-40W4100 wont turn on. Error code red LED blinks 3 times.

Now that I can use. Thanks.

[budm]

Re: Sony Bravia KDL-40W4100 wont turn on. Error code red LED blinks 3 times.

I will see how DC ALERT 1 work.

[lookimback]

Re: Sony Bravia KDL-40W4100 wont turn on. Error code red LED blinks 3 times.

OK. I'm about to open it back up now.

[lookimback]

Re: Sony Bravia KDL-40W4100 wont turn on. Error code red LED blinks 3 times.

Well, I put some hours into this one today. I don't know exactly yet but I'm close. Using the training manual I was able to figure what the DC alert is all about. Basically IC3001 monitors the regulated 5v from IC7132 and the regulated 3.3v from, I don't know where yet. If it detects voltage from IC7132 (the 5v regulator) that is either over or under the limit it shuts down. Also, if it detects the 3.3v is low it will shut down. Using both, the service manual and the training manual I was able to trace out the entire 5v regulator circuit. Its not the IC7132 that's bad. During the few seconds that the set gets power before the relay cuts it off, I was able to test the IC. It gets 12v input. Receives turn on signal (6.67v, not sure if that's high or not.) Output is about 5.2v which should be good. Adj gets about 1.2v. I traced the entire circuit and don't think anything is wrong with it. Only part I'm not certain of is the DC alert transistor. I get no voltage on the DC alert pin and I don't know if that is normal. I think its in the 3.3v circuit IC3001 itself. I'll probably figure it out tomorrow.

[lookimback]

Re: Sony Bravia KDL-40W4100 wont turn on. Error code red LED blinks 3 times.

Well, I made some progress. Sort of. I was right, the the 3.3v power supply was the problem. I found the data sheets for IC7007 and Q7012. I spent a whole lot of time studying the schematics on page 75 of the service manual. What I figured out was that I wasn't getting the 12v source to the Q7012 which I guess is called a syncfet. I checked fuse F7006 and found that I had 12v on one side but only 2v on the other. I jumped it with a single strand of fine wire to see what would happen. Now I get 3.3v output from Q7012 but still something wrong. Now the backlight tries to come on 3 times then I get a code 6. Code 6 is inverter error. If IC3001 detects a high on the inverter error line the unit will make 3 attempts to get the inverter running. In almost all cases the backlights will never light. The exception is if the inverter is starting but its over or under voltage circuits are stopping it. That was all copied from page 58 of the training manual. Well, my backlights are coming on 3 times so its the inverters over or under voltage protection that's causing the shutdown. According to the flow chart on page 55 of the training manual I should check and see if I momentarily have 3.3v on pin 3 of CN6154. I don't have 3.3v but I do have 2v. I don't know just what to make of that. That pin is the inverter error pin and its normally low. Is 2v considered high? If I don't have 3.3v then its still the BU board. I've got to trace the 3.3v after it leaves Q7012. I did notice that on IC7007 I get about 2.5v on pin 2 FB1 but voltage on pin 1 INV1 is 0. I think I'm supposed to have 3.3v on that pin. If so, and I'm not getting it, then something must be drawing it to ground. I think if I'm getting 3.3v output on Q7012 then it must be OK but I don't really know. I wish I had the components needed to make the test circuits that are in the data sheet. So I guess what I should do is trace the 3.3v circuit to all the points its supposed to be at on the BU board. If its everywhere its supposed to be and leaves the board then I guess I'll have to figure out how the OCP and OVP circuits on the inverter board work.

[lookimback]

Re: Sony Bravia KDL-40W4100 wont turn on. Error code red LED blinks 3 times.

No doubt now that its the BU board. Its not Q7012 though. I figured out pretty much how it works. I'm getting the signal from the gate drivers on IC7006. I get 3.3v output. I have 3.3v to almost every place on the board its supposed to be. I've attached a pic. I don't know what this thing is but it might be the problem. I get 3.3v to the top of it but only about 3.0v on the bottom. A third of a volt doesn't seem like much but I guess its enough to set this thing off. Resistances top to bottom are about 9k left and 10k right. There's 2 circled in the pic. Resistances are same on both but the bottom one has 3.3v on all 4 pins. I don't know if its just 2 resistors in one package or what. After the voltage leaves the bottom left pin of the top one it makes its way to IC3001which controls the protect circuits. Voltage there was about 3v.

[lookimback]

Re: Sony Bravia KDL-40W4100 wont turn on. Error code red LED blinks 3 times.

OK I figured out what I think I got it. I don't know how its possible but it looks like I have 2 missing SMD caps. See the attached pics. First one is my board. Red circle is missing caps. The caps go between pin 1 (INV1) and pin 2 (FB1) on IC7007. White circle shows pin 14 (FB2) and pin 15 (INV2). As you can see, caps are present there. Can't see why they would be there and not at 1 and 2. Schematic from service manual shows them as C7051 and C7065. C7051 is 33pf 5% 50v and C7065 is 0.001uf 10% 50v. Pics 2 and 3 are cropped from Shopjimmy pics of both versions of this board. One is very clear and those caps are there. Other is not as clear but you can see one of the caps. My only question is where did they go?

[budm]

Re: Sony Bravia KDL-40W4100 wont turn on. Error code red LED blinks 3 times.

On post 16, does it look like that or some one had worked on that section?

[lookimback]

Re: Sony Bravia KDL-40W4100 wont turn on. Error code red LED blinks 3 times.

16 only looks like that in the pic. I think someone must have worked on this before though. Its had been opened before because screws were missing. Those 2 caps were definitely there at one time because there are depressions in the solder. That was how I noticed it. They didn't look smooth and rounded like other places on the board where there are unused pads with solder on them.

[budm]

Re: Sony Bravia KDL-40W4100 wont turn on. Error code red LED blinks 3 times.

IC7007 needs to have those components back in place, the IC is the dual SMPS (1V and 3.3V): https://cdn.badcaps-static.com/pdfs/...435ea58698.pdf
Is the fuse F7006?