eax64905001 No Pfc Help ?

[ReeceyBurger123]

Hi chaps, have this 32" Lg 32LN5400 with no backlight. Found that the Led drive voltage is only 45v which is way too low it should be 70v to drive 21 Led's. I have checked the Led's and one was bad but after replacing it the issue is still not solved. Found that all Pson and Drive on pins are at what they should be but im only getting 330v across the Pfc caps which again is way too low should be 380v to sustain the outputs.

Any ideas ? If not can someone link the schematic as cant find it thanks.

[budm]

Re: eax64905001 No Pfc Help ?

https://spares2repair.co.uk/lg-32ln5...01-lgp32-13pl1

Is that your board? If it is, it does not have PFC circuit.

PCBA LG EAY62810301 (LGP32-13PL1) Power Supply Unit.
Pictures provided by shopjimmy.

[ReeceyBurger123]

Re: eax64905001 No Pfc Help ?

https://spares2repair.co.uk/lg-32ln5...01-lgp32-13pl1

Is that your board? If it is, it does not have PFC circuit.

Ohh crap yeah, sorry I have had a very bad day and not paying much attention. Hmm so something in the driver is failed as im only getting 45v bud. Any ideas not done much diagnosing yet ?

[ReeceyBurger123]

Re: eax64905001 No Pfc Help ?

Im getting voltage across both caps, one is for the 24v and other is for 12v etc. Getting good 24v but the driver is not being turn on enough.

[budm]

Re: eax64905001 No Pfc Help ?

So the feeding Voltage to the LED boost converter circuit is 24VDC (on C214) and the output to the LED connector without LEDs connected only shoot up to 45VDC and then settle down to 24VDC?
What is the P/N of the LED driver IC801?

[ReeceyBurger123]

Re: eax64905001 No Pfc Help ?

Its at 45v with the Tv on does not go down to 24v. Will get you a Pn in a moment mate.

[budm]

Re: eax64905001 No Pfc Help ?

I would like to know what the feeding Voltage for the Boost converter is, it looks like it is fed from the +LEG of that filter cap C214, so may be the feeding Voltage is too low.

[ReeceyBurger123]

Re: eax64905001 No Pfc Help ?

Image of the Ic, couldnt get a clear shot of the Pn but its:

MAP3202
DR8839GP

[ReeceyBurger123]

Re: eax64905001 No Pfc Help ?

Image of the bottom of the board:

[budm]

Re: eax64905001 No Pfc Help ?

Image of the bottom of the board:

I found the pictures of the board at SJ in post 2.

[budm]

Re: eax64905001 No Pfc Help ?

MP3202 LED driver IC.
http://www.magnachip.com/product/Des...id=MAP3202SIRH

http://www.datasheet-pdf.download/ma...d-blu-drivers/

[ReeceyBurger123]

Re: eax64905001 No Pfc Help ?

Cheers bud, will download and have a play later on or tomorrow

[budm]

Re: eax64905001 No Pfc Help ?

Check the Vin to that Boost inductor L801, when the boost is not on, the Vin will be = to Vout.

[dick_barton]

Re: eax64905001 No Pfc Help ?

Will this schematic help you?

http://obrazki.elektroda.pl/1033688300_1436654733.jpg

[ReeceyBurger123]

Re: eax64905001 No Pfc Help ?

An update chaps, found the I have 0.8v Vcc coming out of the controller which is not high enough to turn on the booster. Got a controller on order

[ReeceyBurger123]

Re: eax64905001 No Pfc Help ?

Just an update chaps, after replacing the Led driver I now have 1.4v Vcc to the mosfets and 70v on the output to the Leds and now have backlight Thanks all video coming soon.

Image of the replaced driver, unfortunately I lifted a trace so this thing doesn't look factory. Serves me right for not using flux !

[snopy44]

Re: eax64905001 No Pfc Help ?

hi sorry if I am posting wrong but need help what is the problem when you get the 3 blinking leds on powering up

[ReeceyBurger123]

Re: eax64905001 No Pfc Help ?

hi sorry if I am posting wrong but need help what is the problem when you get the 3 blinking leds on powering up

Is it on the same Tv ?

[snopy44]

Re: eax64905001 No Pfc Help ?

yes it is the same powerboard just there is nothing about this board on the net

[ReeceyBurger123]

Re: eax64905001 No Pfc Help ?

3 blinking Leds on the standby Led ? If so thats normal, does the backlight not come on though ?