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Sony KDL-40U2000 LCD TV - 4 blinks of death .....

picbits

Well-Known Member
Picked one of these up free yesterday. The previous owner said it was working fine one day and then died with the standby light flashing 4 times, pause 4 times, pause etc etc

The TV works perfectly for around 3-4 minutes then exhibts this behaviour. Googling the flash codes points to the inverter board or possibly power supply board (less common) or terminally the LCD panel backlights (pretty rare).

Some people suggest trying the microfuses onboard the inverter, other obvious things to check are dodgy capacitors etc. Grumpy TV Repair "engineers" seem to suggest the panel backlights are duff and the whole telly should be scrapped.

Anyone in the repair trade with access to the holy grail - Euras or similar have a spare couple of minutes to suggest other things to look at on a component level basis ?

Ta
Dom
 

Nigel Goodwin

Super Moderator
Most Helpful Member
4 flashes is "panel error", it 'could' be a problem on the inverter, but the inverter is part of the panel anyway.

What you need is one with a smashed creen that you could borrow an inverter from.
 

picbits

Well-Known Member
Cheers Nigel - I'll have a look at it when I've cleared enough room in the workshop to fit it in (so in a month or so with a bit of luck lol).
 

Nigel Goodwin

Super Moderator
Most Helpful Member
If it's any help, connector CN3004 is the connection to the inverter from the main board, the block diagram shows pin 1 as panel detect, pin 3 as backlight, and pin 4 as dimmer (pin 2 is panel detect for 26 and 32 inch versions).
 

picbits

Well-Known Member
You're lucky it's only a 40! :p
When she posted the advert for it she described it as a 36"

I had a heart attack when I got there and found it was a 40" - the first thing the stepson said when I staggered to the car with it was "mums going to kill you !"
 

Nigel Goodwin

Super Moderator
Most Helpful Member
When she posted the advert for it she described it as a 36"

I had a heart attack when I got there and found it was a 40" - the first thing the stepson said when I staggered to the car with it was "mums going to kill you !"
You don't 'stagger' with a 40 inch :D

Not even an old one like that.
 

picbits

Well-Known Member
They are ok in the open on the flat but a couple of flights of stairs and a narrow hallway nearly got me ;)
 

unclejed613

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Most Helpful Member
one thing that fails in inverters are the small ceramic disc capacitors, usually something like 10 or 12pf/6kv. they go dead short when they fail, and it causes an inverter error. they're usually right next to the connectors for the pink and white wires. another common failure is for the pink and white wires to get pinched between the sheet metal or poke through the insulation on a sharp corner of the sheet metal.
 
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Nigel Goodwin

Super Moderator
Most Helpful Member
one thing that fails in inverters are the small ceramic disc capacitors, usually something like 10 or 12pf/6kv. they go dead short when they fail, and it causes an inverter error. they're usually right next to the connectors for the pink and white wires. another common failure is for the pink and white wires to get pinched between the sheet metal or poke through the insulation on a sharp corner of the sheet metal.
That's only on certain makes and models, Sony's don't have either of those problems.
 

picbits

Well-Known Member
As a follow up, I've dismantled the television and it appears that F003 (500ma/63v) has blown. It also seems a fairly common problem with these televisions so I'll order up a new one and keep my fingers crossed.
 

picbits

Well-Known Member
It's on the inverter board to the left of the television. As you look at the connector towards the top right of the board, you can see F003 to the left of the large electrolytic.

The one on my board is open circuit and a few other forums have reported that replacing this with a fresh fuse cures the problem. I'm a little skeptical as fuses normally blow for some reason but it's worth a punt.
 

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Nigel Goodwin

Super Moderator
Most Helpful Member
It's on the inverter board to the left of the television. As you look at the connector towards the top right of the board, you can see F003 to the left of the large electrolytic.

The one on my board is open circuit and a few other forums have reported that replacing this with a fresh fuse cures the problem. I'm a little skeptical as fuses normally blow for some reason but it's worth a punt.
Stick a bit of wire across it and see if the set works - THEN (assuming it does) obtain and fit a new fuse.

Occasional failure of those kinds of fuses for no reason is quite common.
 

picbits

Well-Known Member
I was tempted to bridge it (or use my ammeter) but ran out of time when the kiddie got home so tagged on some fuses on an order from RS which should be here today.

I've also got a rather tasty Arcam AVR300 to fix up which may or may not be a failed smoothing capacitor ......

Just out of curiosity Nigel - would you use a T or F type fuse as a replacement ? I've got both on order but as the service manual doesn't include this board, I can't work out if I should go fast or slow blow.
 

Nigel Goodwin

Super Moderator
Most Helpful Member
I was tempted to bridge it (or use my ammeter) but ran out of time when the kiddie got home so tagged on some fuses on an order from RS which should be here today.

I've also got a rather tasty Arcam AVR300 to fix up which may or may not be a failed smoothing capacitor ......

Just out of curiosity Nigel - would you use a T or F type fuse as a replacement ? I've got both on order but as the service manual doesn't include this board, I can't work out if I should go fast or slow blow.
The inverter is part of the LCD panel, so no circuit or spares available - but we don't stock anything other than anti-surge (T) fuses.
 

picbits

Well-Known Member
Hmm the inverter looked removable to me - I didn't prod it too much though but it appeared to have the tube connectors on the left and the power/control connector on the right and a few screws holding it onto the frame. I'll have a better look at it when the fuse turns up.
 

Nigel Goodwin

Super Moderator
Most Helpful Member
Hmm the inverter looked removable to me .
I didn't say it wasn't 'removable' :D

But it comes as part of the LCD panel, from the panel manufacturer - so Sony wouldn't even have a circuit for it themselves.

However, they have made the inverters available individually for a number of different LCD panels - though I suspect they are removed from faulty returned LCD panels.
 

picbits

Well-Known Member
Well I've had 30 minutes out of it so far and all is good. There is obvious wear to the CCFL - they take a little while to warm up in certain places but it seems to be up and runnning :D
 

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