Sony KDL-46HX850 clicks, no picture, standby LED blinks 3 times, repeatedly

[goagola]

Greetings from Nairobi, Kenya. The above referenced unit, now out of warranty, went off quietly while in use, after 4 years of regular use, and was thought to have been responding to a timer setting. Though local power is not clean/reliable, it was protected by a Teledyne power regulator and an APC anti-spike strip. Local SONY say they have no spares for it. As it is now it will click upon connection to power, and the standby LED will blink continuously in groups of three, and a minute or two after power is disconnected, after the LEDs have gone off, it will "double-click," no picture, no sound, no backlight. Any hope that it is salvageable, even via a board replacement? I have had my fair share of sound amplifier builds and repairs, tinkered some with analog TVs, computer motherboards and cellphones to some extent, but this looks daunting, but I am willing to give it a shot. Any help, advice, pointers and directions will be highly welcome, even if it is just as simple as "DONT..."

[budm]

Re: Sony KDL-46HX850 clicks, no picture, standby LED blinks 3 times, repeatedly

3-Blinks is typical error for AUDIO circuit, usually due to DC offset present at the output to the speakers.
The service manual for 46HX855 may be closed enough for your TV.
http://elektrotanya.com/?q=showresul...at2=schematics

[goagola]

Re: Sony KDL-46HX850 clicks, no picture, standby LED blinks 3 times, repeatedly

Thanks Budm, I will give anything a try...

[goagola]

Re: Sony KDL-46HX850 clicks, no picture, standby LED blinks 3 times, repeatedly

Hi Budm, all,

is it normal for the Audio protection to disable the display portion of the set such that I am completely unable to perform the visual diagnostics suggested in these forums. I am not getting any backlight, or indeed any response from the set other than the click and the blinks.

All the same, I will study the schematics to see if there is a pointer in there to the problem. I am also sourcing a replacement BAPS board, hoping that it is the only part that was "hit" by whatever hit the set.

Thanks again for your pointers...

[budm]

Re: Sony KDL-46HX850 clicks, no picture, standby LED blinks 3 times, repeatedly

The protection circuit will shutdown the whole TV, the standby power will still function.

[goagola]

Re: Sony KDL-46HX850 clicks, no picture, standby LED blinks 3 times, repeatedly

Is this protection circuit defeatable somehow?

I've just missed out on a couple of BAPS boards that recently came up at ShopJimmy.com. I am back on the waiting list, but with no availability date indicated, I am tempted to try hacking the "faulty" board. Thinking of putting it on a test-bench, together with its PSU, which I really don't want to add to the casualty list, and running basic component-level tests.

Is there a component/part that is known to fail on this board, something like "the usual suspects" that one can begin with. I hope that that the board is not too tightly integrated to, or dependent upon, its surrounding hardware, to prevent functional testing.

Here is to a "smoke-free" testing...

[budm]

Re: Sony KDL-46HX850 clicks, no picture, standby LED blinks 3 times, repeatedly

It can be defeated for testing, the problem will be getting the diagram that matches your board to find out what is needed to defeat the circuit.

[goagola]

Re: Sony KDL-46HX850 clicks, no picture, standby LED blinks 3 times, repeatedly

Hi Budm,

Much appreciated. Schematics for these are indeed hard to find on the web or elsewhere. The only manual/diagram I've come across so far is the chassis/dis-assembly service manual. It has a wealth of relevant information, but alas no schematics.

I continue to search for these, may be one will turn up. On another note, the manual I have has a section on a "service mode" accessible from the standby mode using the remote. Will the faulty BAPS board allow this?

I intend to poke around the insides of the set this weekend. Hopefully a dead bug may just be loosened out of the works, and the set magically come alive? NOT!

[budm]

Re: Sony KDL-46HX850 clicks, no picture, standby LED blinks 3 times, repeatedly

http://www.shopjimmy.com/catalogsear...ny+KDL-46HX850

Are those all the boards used in your TV?
Can I see the pictures of the whole backside of the TV to see how all the boards are connected together?

[goagola]

Re: Sony KDL-46HX850 clicks, no picture, standby LED blinks 3 times, repeatedly

Had it open this weekend but had no camera. Here is a mobile phone picture with only the back removed, hope it is is clear enough. 4 boards are visible, five if I count the small Wi-Fi module, some under cover. The flat ribbon cable into the triangular BAPS board was very stubborn and for fear of breaking something, it was not touched. This stopped any further dis-assembly into the layer below what is shown in this picture. If there is a catch that releases the ribbon cable, I was unable to locate it...

[goagola]

Re: Sony KDL-46HX850 clicks, no picture, standby LED blinks 3 times, repeatedly

Are there more than one version of the BAPS board for the HX85x series? The board in this set has the black connector for the external speakers on the base/stand near the lower left corner of the triangular board. I've seen others on the internet (same model number etc) with a smaller white connector (like those for 4-wide audio cables) in that same location.

[goagola]

Re: Sony KDL-46HX850 clicks, no picture, standby LED blinks 3 times, repeatedly

Budm, any further insights on this?... Do I get a higher res picture?....

[budm]

Re: Sony KDL-46HX850 clicks, no picture, standby LED blinks 3 times, repeatedly

Turn the TV on and check for DCV on the speakers terminals of each speaker to see if they are present.

[goagola]

Re: Sony KDL-46HX850 clicks, no picture, standby LED blinks 3 times, repeatedly

Hi Budm,

Sorry been away a while, but came back and measured for DC voltage at the speakers. Found none! However, I was able to temporarily "borrow" a working BAPS board from a buddy's unit this past weekend, and with that, lo and behold, the unit came alive!

The backlight subsystem lit up, and both the sony logo and the sound system (white noise whoosh) kicked in for five seconds and then cut out, but the backlights remained on. In subsequent switch-ons, including from the remote controller, the Sony logo did not show on screen, but the sound still came on for five seconds, and then cut out.

For fear of toasting my friend's BAPS board, I resisted the temptation to probe the unit further. I am ordering a BAPS board if and when they become available, and will see if I can revive the unit with that and a software update...

How I wish I could repair my original BAPS board, it "looks" pristine, but simply refuses to work