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Sharp le32d44e

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downunder:

Definitely worth a try. Sounds like a backlighting problem. Have you managed to get into the service menu yet, to check lamp error count and possible cause of failure.

Bruce

Turnip:
Hi folks,

Looked up entry by 'Contrast John' - Think attach, might be useful - Chris.

Managed to sort this one out. The lamp error counter had reached 5 which means the set needed to be started in service mode (hold down input and vol - on tv set whilst applying mains until the letter K appears on the screen, after which press vol - and prog - on tv set to get the service menu). Had no joy doing this though because the ccfl driver IC (BD9883 smd) was going into protection mode and preventing the backlight from operating. To get round this problem I overode the protection by fitting a shorting link across C7558 (smd capacitor) located near the IC.
(C7558 is located about an inch away from the BD9883 driver IC. Both are surface mounted components.)  The set would now start in service mode.
Found that there are some test patterns available in the service mode one of which is a grey screen. Selecting this option showed the problem. The area across the centre of the screen was darker than the rest indicating the centre pair of ccfl tubes weren`t working. This chassis uses 10 tubes driven by 5 inverter transformers mounted in line with them, so before embarking on a tedious stripdown I ruled out the possibility of a duff transformer by swapping the centre one with one of the others. No change of course, so I dismantled the unit and checked the tubes and their holders for any visible problems. None were apparent but replacing the tubes cured the problem. Just needed to clear the lamp error and remove the link
Two were faulty on that one but it seems more common that just one is u/s. Check to see if your dark band is narrower at one side than at the other. If it narrows to a couple of inches it's probably just one tube.
Have found it useful to mark the position of the faulty tube before dismantling fully, so as not to swap the wrong one.
Contrast John.

michael first:
hi,that's right, the 32inch model mounts BD9883FV as inverter controller,so must ground pin#12 to

disable the protection,as Chris writes,citing 'Contrast John'.the OZ964 is mounted on the 26inch

version.sorry

Turnip:
Hi Mike,

Have most Quuq LCD stuff listed since Bruce landed in Australia to sort Panasonic stuff for us folks.

Mind you, little on Plasma - Hate 'em, as my customers have short pockets, and mostly require change from a fiver - Hits the profit margin - Chris.

downunder:

Hi Chris,

Nil desperandum, plasmas are on the way out, but hey, they're just another tv. Certainly beats those colossal rear projection tvs. Still occasionally get a punter who wants one of the monoliths repaired.

Didn't know folks were such tight-asses in your neck of the woods. You'll have to supply them with man-bags so they'll have room for more shekels. Hell, I wouldn't even remove a back cover for 10 bucks.

Bruce

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