Sony KDL-46EX500

[dhoff024]

I have a friend that brought me this TV and asked if I could fix it so I told him that I would try since I have fixed a few TV's with the help of the forum. Basically what is going on is the TV when plugged in the red power light is on. After you press the power button the light turns green and the TV makes a chiming sound 2 times probably about 15-20 seconds apart. After that the TV shuts itself off. The screen remains black and doesn't really do anything that I can see. I did take the back off but did not see anything out of order all the caps look good and didn't notice anything alarming but I did take some pictures of the boards to see if there is something I am missing or something that I don't know of that I should check.

[aaronwt6]

Re: Sony KDL-46EX500

Well, without any further testing I can tell you from personal experience that it's almost certainly a main board issue. I've dealt with quite a few 32, 40, and 46 EX300, EX400, and EX500 series Sony's. My basic finding on them as been that if they are completely dead with no lights or response it's the power supply, and if they are doing the multiple startup scenario you are describing, it's the main board.

Check all your voltages on the supply while it's attempting to start. Most likely, they come up until the TV shuts back down.

[dhoff024]

Re: Sony KDL-46EX500

Well, without any further testing I can tell you from personal experience that it's almost certainly a main board issue. I've dealt with quite a few 32, 40, and 46 EX300, EX400, and EX500 series Sony's. My basic finding on them as been that if they are completely dead with no lights or response it's the power supply, and if they are doing the multiple startup scenario you are describing, it's the main board.

Check all your voltages on the supply while it's attempting to start. Most likely, they come up until the TV shuts back down.

Thanks for the reply I will check the voltage when I get a chance so basically if voltage is ok until the TV shuts off its the main board? Also if the main board is the issue is the only solution purchasing a new board?

[CapLeaker]

Re: Sony KDL-46EX500

Check the BLon (backlight) pin on the PSU. Does the backlight come on at all (maybe for a second or 2)? Check the main filter cap for >360VDC when the tv is on. Also do the flashlight trick on the screen if you do see a picture.
Also post a straight shot of the PSU with the pin out (top left).

[dhoff024]

Re: Sony KDL-46EX500

Just replaced the main board on the TV today and still getting the same issue any other suggestions? I tried the flashlight trick and got nothing so there the backlight I believe is fine. With this mainboard I am getting the red light blinking 6 times when the TV is plugged in but off.

[dhoff024]

Re: Sony KDL-46EX500

Also this time the startup scenario it chimes 3 times instead of 2 times like it did before. I am not sure what the names of each of the boards on the TV are. Obviously I know the main board but what are the names of the other boards and where else should I check. Most other TV's that I have fixed have been cap issues or something where I could pinpoint the problem and replace parts I have never had to us a DMM and check voltage and don't really know where to start if someone could help me with how to begin and where to start with this TV to try to track down the route of the problem I would appreciate it.

[budwich]

Re: Sony KDL-46EX500

Just replaced the main board on the TV today and still getting the same issue any other suggestions? I tried the flashlight trick and got nothing so there the backlight I believe is fine. With this mainboard I am getting the red light blinking 6 times when the TV is plugged in but off.

no sure how to read this as there appears to be some words missing.... "I tried the flashlight trick and got nothing so there the backlight I believe is fine". Is there or isn't there any backlight happening... ever? My "read" would be that you have a backlight issue somewhere.
check fusing on the inverter board.

[dhoff024]

Re: Sony KDL-46EX500

no sure how to read this as there appears to be some words missing.... "I tried the flashlight trick and got nothing so there the backlight I believe is fine". Is there or isn't there any backlight happening... ever? My "read" would be that you have a backlight issue somewhere.
check fusing on the inverter board.

Sorry for the confusion I posted this a while ago and I didn't have access to the TV again to look at it since it is a friends and not mine. I told him that it was a possible main board issue that he could order the board or I would have to look at it further it was up to him so he ordered the board and I just got a chance to go replace the board but that did not work. There was a previous suggestion of trying the flashlight trick to see if I could see picture. I tried the flashlight trick but there is nothing.

So what is going on is when I first got to look at the TV when you turned it on the green light would come up and flash and the TV would chime twice about 20 seconds apart and then shut down and the red light would blink. There was never any signs of the backlight. My friend bought a new mainboard and I replaced it now I am getting the same symptoms but it will chime 3 times at startup instead of 2 but there is still no backlight and the TV will shut down after the 3rd chime and the red light blinks 6 times.

I would like to think of myself as pretty mechanically minded and with direction I can usually fix most problems. With TV's I have mainly been able to fix bad capacitor problems and other small issues I have never really tracked down a problem like this and don't know the names of the boards or which one is which. What board is the inverter board and where do I start? Do I need to check voltage? I know how to use a DMM just don't know where to start and what I should be checking. I am kind of learning more and more with each TV that I am asked to look at its kind of a hobby almost I like to be able to fix things instead of seeing them thrown out.

[budwich]

Re: Sony KDL-46EX500

no problem... the wording wasn't clear so rather than "fill in the words by guessing", it was better to "double check".
You should find the service manual somewhere (and for free)... especially for sony. I think most show that code as issues with the backlighting and since you never see it, I suspect that's where your problem lies. It could be a fuse (doubtful.... but maybe but usually that will mean there are issues further).

Of course, going thru the "tv repair reference library" thread on this forum is a good place to look ... ;-)

[budm]

Re: Sony KDL-46EX500

Training manual. AZ1K Chassis: DKL-**EX301/401400/400/501.
CTV-61 Training manual.
sony_ctv-61_AZ1K_chassis_training_manual.pdf

Page 19:
6X Blink - Backlight System Failure (46” Models)
The 46” models have both a 4X and 6X blink protection mode. The 4X blink will, in most cases, be caused by a defective lamp.
Because all the Backlight HV Inverter circuits are located on the GD2-Board, a 6X blink protection mode will be fixed, in most cases, by replacing the GD2-Board. If the GD2-Board does not repair the problem replace the A-Board. The BL-ON and Dimmer signals come from the microprocessor on the A-Board. A shorted or open BL-ON signal will cause this 3X condition. Also a shorted Dimmer will cause this 3X condition.

[dhoff024]

Re: Sony KDL-46EX500

no problem... the wording wasn't clear so rather than "fill in the words by guessing", it was better to "double check".
You should find the service manual somewhere (and for free)... especially for sony. I think most show that code as issues with the backlighting and since you never see it, I suspect that's where your problem lies. It could be a fuse (doubtful.... but maybe but usually that will mean there are issues further).

Of course, going thru the "tv repair reference library" thread on this forum is a good place to look ... ;-)

Thanks for the help I will check the reference library and see what I find there. I am going to do some more research and see if I can find a service manual online. I will try to keep the thread as up to date as I can but I appreciate everyone's help so far this is the most difficult TV fix I have had so I will be pretty pumped up if I can get it fixed.