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Sony Bravia 40v5500 red flashing light, 6 times.

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downunder:
Ah, that's clearer. See the inverter board on the left. Each CCFL is energised by all those small transformers. Put your fluke on ohms and compare the readings on each transformer. Normally they're a match but if you find one that is of different resistance, you're on the money. Even a 10% difference will throw the protect circuit into a spin. It's the high resistance side we're particularly interested in. Also inspect them for poor connections.

simlock:
Hi Bruce,

Yes i thought it best to post a picture up, give you some idea of my model with the back off, ok i know what board it is now, and what to do, i will go through them steadily to see if any are different in OHM's. ill give them a check also as you say to see condition, i have a good magnifier here i bought for work, and let you guys know what i found, thanks for the advice, and how to check. it for problems, really appreciate it.

downunder:

That's a place to start but those transformers may be OK. You'll find a fuse on the inverter - make sure that's OK - and it looks like the board has "fingers" cut into the extreme edge of the board, which slide into the CCFL sockets for contact. Check these contacts on the back of the board to see if any are burnt/charred or otherwise making poor contact.


Maybe then it's time to get serious about the lamps themselves. No real way to test them other than visually. There are CCFL testers, but like LED testers they only supply minimal operating conditions, i.e. they're apt to tell porkies about the true state of the lamps. Don't try to check the inverter outputs with your Fluke or you might need to retire it if output is present - some serious lamp ignition voltages there.                       Bruce

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