Philips 42PFL3603D/F7 blowing fuses

[jaxmoto]

I have done everything I can find in testing this thing, I'm at the limit of what I know how to do.

Philips 42" LCD

Bought this TV locally and was told it was knocked out by lightning along with a bunch of other stuff in an old lady's home, so her neighbor was selling off what he could.

Fuse was blown and it immediately blows replacements.

The only obvious damage is the resistor above the fuse which fried (second picture). The rings were fried off so I can't tell what it should be. It tests 5.14k, so it isn't open.

I have tested the bridge rectifier using instructions here and elsewhere, everything checked out.

I tried just checking resistance across the mosfets and everything seems to match up (from one to the next they match).

The only thing I found is that about half of the diodes on the board show 0v in both directions, while the other half show OL/.55v.

The first question would be if all the diodes in circuit should be testing properly, or if I actually have about 5 bad ones (these are all on the hot side).

Secondly, where should I go from there?

Thanks, pictures attached.

[budm]

Re: Philips 42PFL3603D/F7 blowing fuses

OK, please take good closed up pictures divide them into 4 or more sections so I can really see all the components, I will need both the top and the bottom sides.
Is there a chassis number on the model number sticker? It will be something like:
42PFL3603D/F7 L09.1
You should also test the components off the board.

[tom66]

Re: Philips 42PFL3603D/F7 blowing fuses

R101A to me looks like it is the Class X safety discharge resistor. It is supposed to fail short circuit on failure (maybe becoming short at higher voltages, like a varistor), so it is failed. It should be of the order of 470k ohm to 2.2Meg ohm. Must have been a really bad failure to damage that, so there's probably more than one fault.

It would also be good if we could get pics of the bottom of the board.

[jaxmoto]

Re: Philips 42PFL3603D/F7 blowing fuses

Ok here are some more pictures. Like I said, all I know is that it supposedly was a lightning strike.

I wouldn't put so much effort into it, but replacement power boards go for about $100 for this set.

This is the best my camera can do.

The chassis number shows LC8.1U LA

[tom66]

Re: Philips 42PFL3603D/F7 blowing fuses

OK, that R101A looks to be a fusible resistor feeding the standby controller, so I figure the standby controller may be bad or one of those diodes in series could be bad too.

[twbranch]

Re: Philips 42PFL3603D/F7 blowing fuses

In my experience a diode or transistor blown will cause fuses to blow immediately. Obviously it depends what the diode or transistor is being used for but I will second tom66 on this one.

[bigpapabooga]

Re: Philips 42PFL3603D/F7 blowing fuses

was this ever resolved? i have a similar prob

[running on empty]

Re: Philips 42PFL3603D/F7 blowing fuses

I am looking for the value of R101A. Mine was charred and cannot tell the colors

[Chris15x]

Re: Philips 42PFL3603D/F7 blowing fuses

If you are still looking, the resistor is the same as R2, 540 ohms.

[sordids999]

Re: Philips 42PFL3603D/F7 blowing fuses

hello

does anyone know the dimensions of the stand screws i have seemed to have misplaced them

[andrew3968]

Re: Philips 42PFL3603D/F7 blowing fuses

If you are still looking, the resistor is the same as R2, 540 ohms.

Where to buy the resistor ? Can't find it anywhere to buy

[tvtimmy]

Re: Philips 42PFL3603D/F7 blowing fuses

If the set keeps blowing fuses, replace u101.

[andrew3968]

Re: Philips 42PFL3603D/F7 blowing fuses

The fuse isn't blown at all. The resistor R101A is burnt . Have two swollen capacitors. Having a very hard time . Trying to buy the resistor 540 ohms . Only found 560 ohms

[dick_barton]

Re: Philips 42PFL3603D/F7 blowing fuses

For testing purposes you could series two resistors to get the value

270 + 270 = 540 Ohms

[andrew3968]

Re: Philips 42PFL3603D/F7 blowing fuses

For testing purposes you could series two resistors to get the value

270 + 270 = 540 Ohms

But after testing it . Where would I find a 540 ohm resistor?

[dick_barton]

Re: Philips 42PFL3603D/F7 blowing fuses

Try mouser and search for 540 Ohms in search box

[andrew3968]

Re: Philips 42PFL3603D/F7 blowing fuses

Try mouser and search for 540 Ohms in search box

Thank you checked it backordered till at least 11/23