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I have a Sony KDP-57WS550 TV. It won't turn on. It clicks

Customer Question

I have a Sony KDP-57WS550 TV. It won't turn on. It clicks then blinks 4 times then clicks again. At first it would turn on after I pushed the on button several times, Now it won't turn on ever, just the 4 blinks. Blinking code description says vertical deflection stopped. I don't want to spend much on it. Is it worth fixing? I know how to solder and use a multimeter.
JA: Sometimes things that you think will be really complicated end up being easy to fix. The TV Technician I'm going to connect you with knows all the tricks and shortcuts. Is there anything else important you think the TV Technician should know?
Customer: I have some of the boards unplugged so I will need to put it back together before I can do any testing.
JA: OK. Got it. I'm sending you to a secure page on JustAnswer so you can place the $5 fully-refundable deposit now. While you're filling out that form, I'll tell the TV Technician about your situation and then connect you two.
Submitted: 11 months ago.
Category: TV
Expert:  Anthony_Infotech replied 11 months ago.

Hello

Welcome

Most likely is the vertical deflection chip has failed that would be the first thing to look at and likely replace the chip do you think you can do that?

Anthony

Customer: replied 11 months ago.
If I can find it on the board and find a replacement chip I can replace it.
Customer: replied 11 months ago.
Is that chip hard to get to?
Expert:  Anthony_Infotech replied 11 months ago.

Its on the D board that is the one with bulky transformer on thick red lead goes to top of CRT,its IC5101 on that board try resoldering the chip and surrounding area then just replace it if no joy, you should get a chip from www.mcmelectronics.com its a LA7804S

Let me know if you need more help remember the question never closes even after rating

Please consider rating the answer positively there will be a rating bar of stars usually at the top of the page with this post thank you, ***** ***** positively enables me to receive credit from the site thanks again, the session will remain open and stay open as long as you need it, if you have any concerns please just let me know and I will answer any queries you have

Many Thanks

Anthony

Customer: replied 11 months ago.
Is the D board the flat one on the bottom left side looking in the back of the TV? What location on the board is it? Do I need to remove the board to get to the back side to solder it? Would Radio Shack possibly have it?
Customer: replied 11 months ago.
I unplugged the TV. Is there a dangerous high voltage capacitor that could get me?
Expert:  Anthony_Infotech replied 11 months ago.

The D board is usually on the left you cant miss it! it has the horiz output transformer on look for the thick red lead that goes to top of tube CRT

I cant rem where it is exactly on the board but it will have a heat sink attached which makes it very easy to find

Radio Shack will NOT have the chip you need to google its number

Expert:  Anthony_Infotech replied 11 months ago.

You do need to be careful and wait a bit before doing anything set unplugged from wallpower

Anthony

PS please remember the rating I will provide further support

Expert:  Anthony_Infotech replied 11 months ago.

Do you still need help please?

Customer: replied 11 months ago.
I found the IC5101. Will try resoldering it tomorrow. Had to pull the whole board out to get to it.I thought I found the problem when I was taking the board out . I found that one of the large red leads that comes from the bulky transformer had been spliced and had come unsoldered and wrapped in tape. I resoldered it and for 3 times the TV turned on and off. Then I moved the TV and plugged some inputs into it and it would not turn on, just the 4 blinks then a final click like before. So I guess it worked intermittent like it used to do like I stated in my original posting.Like I said tomorrow I will try resoldering and test again. I will let you know.
Expert:  Anthony_Infotech replied 11 months ago.

OK now that you have found it solder up the pins of the chip well and have a general resolder of any suspicious joints in the area, you may need to replace the chip if that does not work

Anthony

Customer: replied 11 months ago.
I touched up the solder pins on and around the chip even though none of them looked cold. I went ahead and ordered a new chip. I think I will wait until I get it and just install it before I put the board back in to try since there would be quite a bit of work hooking everything together to test. That way I just do it once since the chip was cheap off ebay under $8.00. So I will get back to you in about a week. Thanks for your patience.Norman
Expert:  Anthony_Infotech replied 11 months ago.

OK thanks

Anthony

Customer: replied 10 months ago.
Posted by JustAnswer at customer's request) Hello. I would like to request the following Expert Service(s) from you: Live Phone Call. Let me know if you need more information, or send me the service offer(s) so we can proceed.
Customer: replied 10 months ago.
I received the chip but then realized my solder pencil is crappy and I need a vacuum solder sucker to remove the solder from the chip leads. Any stores with those items are closed today so I will pick them up tomorrow after work and try replacing the chip. Will let you know after I test it.Thanks, Norman
Expert:  Anthony_Infotech replied 10 months ago.

OK

Customer: replied 10 months ago.
This is going to be slower than I wanted or expected. I could not find a good solder pencil or solder sucker around here so I had to order one on internet. I want to do it right. So will get back with you when I can move forward on fixing it.Later and thanks, Norman
Expert:  Anthony_Infotech replied 10 months ago.

OK

Customer: replied 10 months ago.
I just got back from a funeral out of state and received a new solder pencil kit. I replaced the IC5101 and tested. It did not turn on, only the click, 4 blinks then a final click. The same as before. So I need some more help.Also, it is my understanding that I am not to give any rating until I am satisfied that the problem is fixed. That is correct, right?Thanks,
Norman
Expert:  TV Tech1 replied 10 months ago.

More than likely you lost the + or - 15 Volts supply to that IC you installed. Pin 2/R5114 is your +15 and Pin 4/R5105 is your - 15 supply on that IC you replaced. Now here's the FUN part - There could be ANY variation of resistors/jumpers supplying those voltages to that IC. Sony made it vague to accommodate different sizes of TV screens. I'd expect those resistors to run in the 1.3 to 3.3 ohm range, they act as a fusible link/resistor, and are usually 1/4 watt resistors.

That may help you get back on track with that vertical problem

Customer: replied 10 months ago.
Where can I find a convenient ground on the board?
I looked at the resistors around the chip that i replaced. I finally found them and on the board is marked +15V by the R5114 and-15V by the R5105. They were hard to find because it is crowded and small writing. I got someone coming tomorrow to help me test it. Will let you know then.
Thanks, Norman
Expert:  TV Tech1 replied 10 months ago.

Where can I find a convenient ground on the board? I always use the RCA jacks on the back of the TV set for ground, using an alligator clip. The outside of an RCA is ground

Customer: replied 10 months ago.
Tested the voltage of + and - 15V test points when turning on TV during the 4 blinks. It is 0 Vollts on both. I know I have good contact.
Norman
Customer: replied 10 months ago.
Actually the voltages are -0.480 on the +15V test point and -0.035 on the -15V test point. It is the same both when I press the on button and the TV is going through the 4 blinks before I try turning it on. What do I check next?Norman
Expert:  TV Tech1 replied 10 months ago.

On the 15 volt supplies, have you checked for shorts to ground? Although I doubt the Vertical Output IC is shorted, perhaps the 15 volt rectifiers are shorted. You need to know if there is a short or not. If not, then the resistors R5114 or 5105 mentioned previously may be burned open

Customer: replied 10 months ago.
I checked for short to gnd at both the + and - 15 V test points. I got 1.2 megohm and 1.7 megohm on the -15V test point depending on which direction I had the meter. I got 4.7 megohm and 2.5 megohm on the +15V test point depending which way I had the meter.However I am really confused with the circuit board in the area of where it is labeled R5114 and R5105. On the top of the board where the resistors are labeled are jumper wires which are also the test points for the + and - 15V there are NO resistors there. I pulled the board out thinking they might be in the bottom and there are no resistors there either. I can send pictures if you want. Could those resistors be in another section of the board that feeds these test points?
Customer: replied 10 months ago.
I traced the lands back from the 15 V test points and one direction they go to the vert deflection IC and in the other direction they go to capacitors, not resistors.
Customer: replied 10 months ago.
The test points for 15V are short jumper wires. I think these jumpers are the resistors with 0 ohms. I can send pictures if you want. What can I check from here?Thanks, Norman
Expert:  TV Tech1 replied 10 months ago.

Could those resistors be in another section of the board that feeds these test points?

Most likely not...Sony has a tendency to modify and likely left those resistors out of the circuit.

The key is, do you have BOTH the + and - driving that vertical amp? You need both to power it up or you get the 4 blink code.

Customer: replied 10 months ago.
I don't have either the + or - 15V to the vertical amp. Are there other test points on the board where I can trace back to the supply for those voltages
Customer: replied 9 months ago.
What can I check next?
Expert:  TV Tech1 replied 9 months ago.

Well, the HORIZONTAL OUTPUT circuit drives a transformer that powers up the Vertical circuit, (first picture) and the vertical circuit (2nd picture) shows where that + and - 15 volts connect.

Customer: replied 9 months ago.
First, thanks for the electric schematics. They were helpful. Unfortunately I got no voltage at the output or input to the transformer.
What do I check next?
Norman
Expert:  TV Tech1 replied 9 months ago.

Hmm, sounds like you lost DC voltage to both sides of the transformer. I'd certainly be looking for DC current limiting resistors being open from the power supply section, or near the transformer. I'd also check the drive transistors on both sides for shorts, also check the resistors for bad solder since that's the most likely problem.

So -

R6613 and R6614 in the FIRST JPG (that's the fuse/resistors for the vertical section)

is coupled to the 135 V supply through this circuit (page 66 of the service manual -see picture)

I'd want to see if the 135 Volt circuit is dead. Keep in mind your TV is likely shutting down fast enough that you can't read any voltages, and you have to do a resistor check for open resistors. They are essentially FUSES for each circuit section. My guess is the 135 Volt main power supply section has blown one of its fuses/resistors indicating WHERE the shorted transistor is.

The four blink fail code is only indicating that the Vertical has been triggered....not that it's actually failed.

You would have to check the - Horizontal output section, High Voltage Transformer output section, 135 Volt power supply section. Those are the heavy loads on the 135 Volt power supply section.

I should ask if you have your own service manual for the AX-1 chassis - do you?

Customer: replied 9 months ago.
I need to ask some questions before I start checking resistors. I do not have a service manual. I do not have the 135 Volt supply at the junction of C5204 and FB5201. And I do not have any voltage at the other side of the transformer at junction of D6606 and C6615. Since they are input to a transformer I assume they are AC Volts but I checked them with the meter on both AC and DC. There was also two test points on this board of 135 and 68V and I do not have V at them either.Will I need to unsolder one side of those resistors to check the Resistance of them? Before I do that I feel that I do not have any supply voltage coming into this board because I haven't been able to find a voltage anywhere I have tried on it and maybe that is what I should be checking. All of my voltage checks have been done while the 4 blink code is flashing on the front of the TV.And no I do not have a service manual.Thanks, Norman
Expert:  TV Tech1 replied 9 months ago.

Will I need to unsolder one side of those resistors to check the Resistance of them?

Just turn off power to measure for resistance.

I do not have the 135 Volt supply at the junction of C5204 and FB5201. And I do not have any voltage at the other side of the transformer at junction of D6606 and C6615.

Hmm, I think we need to move to our 135 Volt source if those are dead.

KDP57WS550 AX-1 chassis

Aha!

The dreaded MCZ3001DA ICs run the power and Horiz /HV circuits on this chassis. I thought the AX-1 was too new for that IC. Kills the 135 Volts. They're located on the D Board real close to the High Voltage transformer, and are lableled IC6400 (power) and IC8002 (high voltage/horiz).

Here is a source for those, replace both for starters.

http://www.ebay.com/itm/MCZ3001D-MCZ3001DA-MCZ3001DB-2pcs-ORIGINAL-2-IC-Socket-USA-FREE-SHIPPING-/280804243230

See the picture for where those ICs are located close to each other on the D board. They're Long black 18 pin ICs. I hope you have some solder-wick, solder, and a soldering iron.

Customer: replied 9 months ago.
I got real ambitious tonight and found a Sony forum website and tried some of the suggestions for the same code of 4 blinks. Mostly it suggested the same checks as you have already. Then it talked about checking the PS that comes into the G2 board which apparently feeds the D board via CN6901on G2 to CN6401 by IC6400. Well I had Voltage of about 120V dc with TV plugged in but off and 347V dc during the 4 blinks at the CN6900 which is good. However at CN6901 and/or CN6401on the D board I had about 0.022V during the 4 blinks and it slowly dropped back to 0V after the 4 blinks. SO I am thinking that voltage is not going to IC 6900 and 8002 because of a problem in the G2 board.
Does this make sense to you and if so what should I check next on it?
And yes, I do have some solder-wick, solder vacuum sucker, solder and good sharp point solder iron.Thanks, Norman
Expert:  TV Tech1 replied 9 months ago.

IC6900 on the G2 board sends power to CN6901 and/or CN6401on the D board . G2 is a LOW voltage power supply system separate from D board's high voltage power supply. It shuts off if there is no power on CN6900 - you stated " Well I had Voltage of about 120V dc with TV plugged in but off and 347V dc during the 4 blinks at the CN6900 which is good"

Umm, what did you have at CN6900 before and after you pressed the power button? When you get the 4 blinks, the voltages are worthless because the TV has already shut down. When you power up the TV...that's the most important readings

If you had 347 volts on CN6900 and then nothing...that's your TV's power relay on the A board clicking on and off. Sony uses a voltage doubler to convert RAW AC 120 V to a RAW DC to supply ALL power to ALL converters. And yes, G2 does use that same IC I mentioned previously. I've never had that one go bad, just the 2 on the D board.

Now if you had a 9 blink code....I'd send you further upstream, and closer to the AC power. But I won't do that.

Hmm, looks like JA has turned on the automatic rating system. I'm not ready for their auto-nag boxes to pop up....ignore them and do not rate me yet

Customer: replied 9 months ago.
Your answer: Umm what did you have at CN6900 before and after you pressed the power button?
My reply I had 120v dc before and about 347v dc after pressing the power button.I replaced ICs 6400 and 8002 and reinstalled the D board and tested it tonight. I still got the same results: a click, then 4 blinks and final click and then nothing. What do I need to check next?
Thanks, Norman
Expert:  TV Tech1 replied 9 months ago.

Ok, the G2 board is good, seems to have passed the test.

We move back to the D board and look closer at the DVcc voltage that powers up the 15 Volt Vert section.

Here is our list of things to check on the D BOARD - see picture.

Now we KNOW we do not have the 15 Volts because the DVcc was also dead on the D Board. That's why we checked that G2 Board. G2 is delivering even AFTER the TV triggers the 4 blink code. So we must have that 135V DC on the FET on the NEXT Pictures, but do we have the Horiz signal /Horiz Pin signal activating that FET OR the Horiz Driver? You might want to check BOTH AC and DC readings on the highlighted sections of the NEXT pictures I gave you.

Customer: replied 8 months ago.
I have 0 volts both on AC and DC scale both before and during the 4 blinks at the 135V locations on both sides of Q5201.At the 1000V H pulse location of Q5001 I am getting 0V on both AC and DC scales both before and during the four blinks.At the 12V signal of Q5001 I am getting 3.07V AC before attempting to turn on and 3.17V AC during the four blinks. On the DC scale I get 0V both before and during the four blinks.
Thanks, Norman
Customer: replied 8 months ago.
What do I need to check or look at next?
Thanks
Expert:  TV Tech1 replied 8 months ago.

Well, we know we're not getting the 135 Volts to power up the Horizontal circuit...and I decided to look at WHY the G2 board "supposedly" works but doesn't deliver the 135 Volts to the D board.

So last night, after I got off work I pondered your issue...then remembered I had a training manual for your TV model.

That, at least gives us a different frame of reference on how you start your TV up.

I'm still studying this "start up design" right now, but it looks like the G2/Q Box does fire up the Main power circuit which provides the 135 V to the Horiz Drive circuit...that means the MAIN power circuit has to be dead, and I think that was one of 2 circuits you replaced the IC in.

HIGHLIGHTS -

Sony KDP-57WS550 AX1 Chassis

what did you have at CN6900 before and after you pressed the power button?
My reply I had 120v dc before and about 347v dc after pressing the power button

I replaced ICs 6400 and 8002 and reinstalled the D board

IC6900 powers up IC6400 which powers up the 135V

IC6900 on the G2 board sends power to CN6901 and/or CN6401on the D board

I have 0 volts both at the 135V locations on both sides of Q5201.

So we have to find that 135 Volt SUPPLY problem

Picture #1 - Power supply Block, Startup Description

Picture #2 - 135V Primary Power circuit - IC6400 primary test points highlighted in yellow

When troubleshooting the AX-1 chassis power supply system, keep this sequential DC Start voltage structure in

mind. For example, if the HV power supply fails, it may be actually a failure of the Primary Power Supply, which

supplies the DC Start voltage to the HV Power Supply, or the problem could be further up in the system in the QBox

Power Supply, which supplies the DC Start voltage to the Primary Power Supply.

Customer: replied 8 months ago.
I checked the voltage at pin 8 of IC6400 where it should be 15.5V. This is on the 2nd drawing that you sent me last. I think this should be DC volts since on the 1st drawing is shows the Q Box output to 'D' board as DC start voltage. On DC scale I get about negative .2V before turning on and neg 93.0 V during the 4 blinks. On the AC scale I get about 56.0 and 60.0V respectively.
At the plus 135V output of L6505 I can't measure it because it is flat mounted, but on both sides of R6590 I get 0V always on both AC and DC. This is also on the 2nd drawing you sent me.
Where do I go from here and what do I check next?
Thanks, Norman
Expert:  TV Tech1 replied 8 months ago.

shows the Q Box output to 'D' board as DC start voltage. On DC scale I get about negative .2V before turning on and neg 93.0 V during the 4 blinks. On the AC scale I get about 56.0 and 60.0V respectively

I can tell those readings are wrong because you are connected to the wrong grounding point.

There's Secondary ground, and then there's DC ground. DC ground is usually the one you want, and I connect to the RCA inputs using an alligator jack and jumper inserted inside the RCA jack. Note the picture where I highlighted the different grounds. You may have to verify this but the ground that is V-shaped should be DC/Rca (green color). The 135V oddly enough seems to be regulated by the AC ground point, but I think that may be

a separated/isolated ground. Yes it is. You have to ground to the points with the magenta line to get a good DC voltage measurement. Pick one of the points highlighted with magenta for your 135 V DC power reading. THAT READING IS WHAT POWERS UP YOUR CIRCUIT CREATING THE 4 BLINK PROBLEM.

pin 8 of IC6400 where it should be 15.5V -ground that to the RCA jack

135 Volt supply - ground to either C6512 or D6508's negative side- all those points should be connected to each other.

Customer: replied 8 months ago.
When I checked pin 8 of IC6400 I did use the RCA jack the my reading on that should be accurate. Those were -0.2V before turning on and -93 V during the 4 blinks.I did use the wrong ground when checking for 135V. Using the secondary ground I have attempted to check for 135V but without removing the board and raising inductor L6505 to get to the leads it is not possible because it is flat against the board. So I used pin 7 of IC6503 as ground and checked the voltage at both sides of R6590. I got 0V both before turning on and during the 4 blinks on both sides of R6590. I also checked for a voltage drop across R6590 and got 0V there which makes sense since I got 0V on both sides. Is this sufficient or do I need to actually check the output of L6505?Thanks, Norman
Expert:  TV Tech1 replied 8 months ago.

R6421 - did you get any voltage on that? That's what powers up the whole circuit. Pin 8 is only half of the start up circuit. Odd voltages though...there must be a unique ground point for that pin, but it does show activity during startup. Don't worry about L6505, R6590 works as that test point.

You replaced IC6400, so we know that should be good.

Customer: replied 8 months ago.
Across R6421 I get very close to 0V both before and during the 4 blinks on both AC and DC.At the junction of R6421 and R6429 I get about .2V DC and 55V AC before turning on the TV. I get 92V DC and 59 V AC during the 4 blinks. These are to chassis ground.If you could tell me if I am looking for AC or DC volts it would help.What next?Thanks, Norman
Expert:  TV Tech1 replied 8 months ago.

Check Connector CN6400 for DC voltage on the D Board, you should also hear a click from the rectifier relay when the TV is turned on, not a double click...just one click. That's your missing power on R6421. CN6400 is a 2-wire plug on the D board, right by R6421. Use that plug as your ground point, one side is ground for the IC and should have about 170 Volts DC on it after the relay clicks, and should stay on all the time.

Customer: replied 8 months ago.
OK, when I press the power button I do hear a click that seems to be coming from sort of the lower middle of the TV, separate from the click that is one of the double clicks. I get a steady 333V DC on C6400 after the relay clicks, then after the 4 blinks the V starts dropping back to near 0V in the next 20-30 minutes. what next?Thanks, Norman
Expert:  TV Tech1 replied 8 months ago.

Well, we are getting power, but not getting 135V DC. The Q-Box should be turning on your Primary power supply\IC 6400...perhaps we should double check the voltages using CN6400's ground line for that start up voltage listed in the previous picture. Check pin 8 and pin 1 -see what they are doing. If pin 8 is low...I'd suspect the Q Box's power supply is dying, and killed by either the 9 or 5 Volt lines it supplies. There's a couple plugs we unplug to see if the supply is bad, or the loads are bad. Back to pin 8 to see if we have DC voltage or not to CN6400's ground.

Customer: replied 8 months ago.
I am getting about 333V on pin 8 and 331V on pin 1 using the brown lead into CN6400 as ground. Those voltages show up as negative. What's next?
Thanks, Norman
Expert:  TV Tech1 replied 8 months ago.

using the brown lead into CN6400 as ground. Those voltages show up as negative. What's next?

That must mean the brown lead is the positive, not ground. Use the other lead as ground, see what those readings turn out to be. Pin 8 and 1 should have a positive voltage reading.

Customer: replied 8 months ago.
Using the blue lead as ground I get approximately +1.6V DC on both Pin 1 and Pin 8. Now what?Thanks, Norman
Expert:  TV Tech1 replied 8 months ago.

Alright, we got to get to the G2 board and test for Power to drive the power supply start up on pin 8 that you checked.

I'll give you pictures here, it's about the same design as you've been working on. Check the connectors, pin 1 and pin 8, but use the ground on CN6900 (blue)

OR

switch to the CN6400 on the D board if you get ODD DC voltages

Customer: replied 8 months ago.
OK, I get +2.9V DC on Pin 1 and +18.2V DC on Pin 8. Since Pin 18 was highlighted in yellow I checked that and got +333V DC. Those are pretty close to the readings shown on the G2 board drawings so I hope that is a good thing.I also checked the junction of D6908 and C6918 since it was highlighted and I got +1.6V DC which is quite a difference from the drawing so maybe that is some of the problem. What do I check next?Thanks, Norman
Expert:  TV Tech1 replied 8 months ago.

I also checked the junction of D6908 and C6918 since it was highlighted and I got +1.6V DC

HMM, That's LOW...low DC voltage. That drives your power supply for your DEAD vertical power supply. The one that triggers your 4 blink code. That's probably the reason you get your 4 blink code. If it's low, it could be that resistor is open, the cap C6918 is leaky...or the 5 or 9 volt supply could have a short on it. Go back to the picture, you see there is a 15 Volt supply to pin 8 on that IC? Check that 1st, IF it's low then the 9 or 5 Volt is likkey low too. There is a plug on the G2 board that can disconnect those supplies, yet keep that IC running. If they're marked, disconnect that plug, if not get back with me if that pin 8 voltage is NOT 15 Volts. If it is 15 Volts, check that diode/cap /resistor/D6908/C6918/R6925. Probably low voltage isn't letting the vertical power supply even start up.

Customer: replied 8 months ago.
I checked the 15.6V supply to pin 8, I get +18.2V with the 9 and 5 volt connector plugged in. I went to the 9 and 5 volt plug. Without unplugging it and using the ground that is on the same plug I get 9.1V and 4.95V. With that connector unplugged I get the same 9.1 and 4.95 volts. With the connector unplugged and going back to the blue wire for ground I get 15.2V on pin 8.Hooray Maybe. I think I found something. I had trouble getting the multimeter leads on R6925 with the G2 board in place but I could not get a R value across it and I think the leads were making contact. Also the resistor leads look blackened and corroded and the color code rings on it look to be burned off so it appears to have gotten hot.The D6908 seems to be OK and I don't know how to check a capacitor with a multimeter but with the physical condition of the resistor that probably doesn't matter.It is late now and I need to go to bed, I need to be at work at 5:00 AM. I will pull G2 board out tomorrow. Is there anything else I should check before I pull the board? If I need R6925, what is the R and wattage?Thanks, Norman
Expert:  TV Tech1 replied 8 months ago.

Sounds like that resistor is burned open/high resistance. Which means the power IC never got power. THE G2 power supply is working, but it's not delivering power to turn on the previous power supply we were testing that provides the 135 Volt DC and Vertical power. I'm pretty sure you replaced that IC, so it may only require that R6925 .

You replaced IC6400, so we know that should be good.

R6925 is a 10 ohm 1/4 watt resistor...you can use a 1/2 watt resistor to replace it since they're easier to find. Got a Radio Shack near you?

You don't need to pull the G2 board, but go back to the D BOARD and check another resistor on that since the resistor is burned on the G2. NEAR Connector CN6401 should be a Resistor R6422...it's a 1/2 ohm 1/4 watt resistor that delivers that 15 Volts to IC6400 pin 8 to power it up.

See the picture --

Now THAT wasn't too hard...was it?

Customer: replied 8 months ago.
I was so optimistic but it turned out depressing. R6925 was definately bad but there is apparently another problem. It still does the 4 blinks and doesn't turn on. I checked the other resistor that you suggested R6422. R6422 is good. I am sure we are both equally disappointed.What should I check next?Thanks, Norman
Expert:  TV Tech1 replied 8 months ago.

You replaced IC6400, so we know that should be good OR IS IT?

At this point in time, we should have all our startup voltages in IC 6400 for it to turn on and get the 135 volt main supply

20fa16d2-835d-4937-96fb-216c3e3d58e1_Untitled - 1.jpg

Connector CN6400 for DC voltage on the D Board-brown lead into CN6400 as ground

I'd check the 135 volt supply and any other power supply lines on the secondary for direct shorts next, keeping in mind the horizontal circuits must start up before the vertical gets turned on by the TV set.

http://f01.justanswer.com.s3.amazonaws.com/TV-Tech1/20fa16d2-835d-4937-96fb-216c3e3d58e1_Untitled+-+1.jpg

Expert:  TV Tech1 replied 8 months ago.

First url link is broken, 2nd is the same link - block diagram of IC6400 power supply. Let's see if those power supply lines have any shorts or low ohms on them. By low ohms I mean less than 1000 ohms.

Check IC 6400's pin 8 using the same ground used on your last Q-box testing, Check IC6400 pin making sure it's getting powered up. Then move on to the Brown wire ground to test that you're getting the 300+ DC on the power driving the IC6400. Lastly, check the output voltages on that supply for shorts and see if the voltages come alive or you get a "bump" of power when turned on. If it doesn't "bump" that's when you check them for low resistance.

Customer: replied 7 months ago.
I need to travel about a 1000 miles away to visit my sister this weekend and next week so I am real busy this week getting ready. I don't have time now to do any checks so I will put it on hold until the week of June 6, then I will get back with you and continue. Until then best regards,Thanks, Norman
Expert:  TV Tech1 replied 7 months ago.

Ok, see you June 6