help with a Philips 47" LCD power fault

[Mikeyboy2007]

hi huys a friend asked me to have a pop at repairing his 47" philips tv, i took off the back and noticed 6 caps where leaking so replaced them, tried switching on and still no standby LED so tested the 3 fuses on the PSU of which one had blown (ceramic fuse) i then replaced with a time delay 1A Glass fuse and as soon as i plugged tv back in the fuse popped but has also burnt something out under the fuse aswell, can anyone tell me what could be the problem ?

[tom66]

Re: help with a Philips 47" LCD power fault

May be a fusible resistor - would need some more detail of the board to be sure.
Part #s, detailed images of top and bottom of board, etc.

[Mikeyboy2007]

Re: help with a Philips 47" LCD power fault

Does this help Tom ?

[tom66]

Re: help with a Philips 47" LCD power fault

Need one for the bottom side of the board (green side)
Also did you use Samwha capacitors in a re-cap job...? Were they original or salvaged?

[Mikeyboy2007]

Re: help with a Philips 47" LCD power fault

Sorry whats Samwah capacitors ? And i just replaced original caps with new ones.

[Mikeyboy2007]

Re: help with a Philips 47" LCD power fault

Hi tom 4 of the caps replaced where samwha and the 2 470uf ones cant see a brand just says C7E but there is also a logo that looks like the samwha logo. These are the pictures of the green side and a close up of the green side of the board where the fuse blew.

[tom66]

Re: help with a Philips 47" LCD power fault

So they aren't causing your problem but they could do in a month's time, why use such rubbish when you can buy genuine Panasonic/Rubycon from CPC with only £5 min order (that bunch of caps would meet that order) with 3 days delivery.

[tom66]

Re: help with a Philips 47" LCD power fault

Check each of the diodes D101A thru D for shorts. check D160.
Odd fault, can't see what R5 exactly does - maybe some kind of supply for the relays - but if so why is it burnt.

[vinceroger69]

Re: help with a Philips 47" LCD power fault

might help?
http://translate.google.co.uk/transl...24%26bih%3D631


this is direct link may need to translate it
http://www.teleservice-depannage.com...cd-philips.htm

[budm]

Re: help with a Philips 47" LCD power fault

That fuse is for feeding B+ to the STBY power supply SMPS IC U101, more likely there is shorted circuit in the IC or related parts. Check to see if R101 is also open circuit. Check the resistance on the two legs of cap C102A to see if it shows really low resistance.
That R5 is the fusible resistor for the feeding the rectifier diodes 101A~101C (check these dioded to make sure they are not damaged also) to run the SMPS IC in STANDBY mode, once the board get the PSON then the PFC Voltage booster will kick in then the B+ will be fed from D160 to run the STBY power supply.
Get the P/N of U101.
http://www.shopjimmy.com/philips-272...pply-unit.htm#


What is the model and chassis numbers of this TV?

[Mikeyboy2007]

Re: help with a Philips 47" LCD power fault

So they aren't causing your problem but they could do in a month's time, why use such rubbish when you can buy genuine Panasonic/Rubycon from CPC with only £5 min order (that bunch of caps would meet that order) with 3 days delivery.

got them out of Maplin for quickness, if it did the trick he was gonna buy Panasonic caps from ebay as i advised.

[Mikeyboy2007]

Re: help with a Philips 47" LCD power fault

Check each of the diodes D101A thru D for shorts. check D160.
Odd fault, can't see what R5 exactly does - maybe some kind of supply for the relays - but if so why is it burnt.

Tom, checked D101A thru D for shorts and all are fine. im unsure why R5 has burnt out think this may have happened after caps where replaced and tv was switched on as fuse blew 2-3 seconds after tv was plugged in.

[Mikeyboy2007]

Re: help with a Philips 47" LCD power fault

That fuse is for feeding B+ to the STBY power supply SMPS IC U101, more likely there is shorted circuit in the IC or related parts. Check to see if R101 is also open circuit. Check the resistance on the two legs of cap C102A to see if it shows really low resistance.
That R5 is the fusible resistor for the feeding the rectifier diodes 101A~101C (check these dioded to make sure they are not damaged also) to run the SMPS IC in STANDBY mode, once the board get the PSON then the PFC Voltage booster will kick in then the B+ will be fed from D160 to run the STBY power supply.
Get the P/N of U101.
http://www.shopjimmy.com/philips-272...pply-unit.htm#


What is the model and chassis numbers of this TV?

Tom, IC U101 looks like it has a leg burnt right at the top just before going into the IC itself, im not sure how to check if R101 is open circuit maybe you can advise ? i tried and was giving me all different readings from 2 pins on one side to 4 on the other side. two legs of cap C102A show 283 both ways,

[budm]

Re: help with a Philips 47" LCD power fault

The SMPS IC is bad. Can you still read numbers as printed on top of the IC.
You just check the resistance between the two leg of the resistor R101, no power to the unit of course.
When fuse is blackened like that, it has really shorted circuit, by now the short circuit is probably almost blew open/ resistance went up by now that is why you are reading 280 Ohms.

[Mikeyboy2007]

Re: help with a Philips 47" LCD power fault

the number on top of the IC is VJ07 FS0510 but cant seem to find any on ebay searching either of this codes ? where could i get one ? will it just be a case of replacing the IC, Fuse and resistor ? or will it have done more damage overall ?

[kasfamily]

Re: help with a Philips 47" LCD power fault

[Mikeyboy2007]

Re: help with a Philips 47" LCD power fault

thanks Kasfamily, does anyone have any info on the resistor that blew below the fuse. R5 on the board, also will replacing the IC, resistor and fuse fix the problem of it popping ?

[budm]

Re: help with a Philips 47" LCD power fault

Post 10:
"What is the model and chassis numbers of this TV?"

[Mikeyboy2007]

Re: help with a Philips 47" LCD power fault

also on ebay can only find same IC but with VJ50 and VB26 on top but the one on this board has VJ07 can anyone advise ?

[Mikeyboy2007]

Re: help with a Philips 47" LCD power fault

Post 10:
"What is the model and chassis numbers of this TV?"

Does this info help. Thanks