Philps LCD TV Some time no back light

[sam_sam_sam]

The other night I turn on this TV and all I got was sound turn back off waited about 30 seconds and turn back on and work agian

Once in a while when you turn this tv it just has one color on the screen if you turn it off and wait 30 second and turn it back on every is ok again

I begin to think that one or more caps may have a higher than nomal ESR reading

Do you think that I am right track or is some thing else going on here

[retiredcaps]

Re: Philps LCD TV Some time no back light

Model number?

[sam_sam_sam]

Re: Philps LCD TV Some time no back light

Model # is 42PFL5332D37

I have to wait to take this TV apart

unless you think I need to before then

until I have a desoilering gun which is on back order until 2-20-2012

heating element when bad in it

[retiredcaps]

Re: Philps LCD TV Some time no back light

Model # is 42PFL5332D37

Is it 42PFL5432D37 by chance? If yes, there are 3 Capxon 1500uF 35V capacitors that are bloated or will bloat. They supply 24V DC to the master and slave inverter.

[sam_sam_sam]

Re: Philps LCD TV Some time no back light

Model # is 42PFL5332D37 what about this one

[PlainBill]

Re: Philps LCD TV Some time no back light

Philips 42PFL5332D37 and 42PFL5432D37 use two different chassis; the EJ3.0U LA and TPM2.0U LA respectively. The power supplies may or may not be the same.

PlainBill

[sam_sam_sam]

Re: Philps LCD TV Some time no back light

I guess it time to take apart and check the caps on the power board with an ESR meter

Thank for your help

[sam_sam_sam]

Re: Philps LCD TV Some time no back light

I found this cross ref

[sam_sam_sam]

Re: Philps LCD TV Some time no back light

Here are some photo of this TV set


Top left photo shows the caps under the heat sinks and how they hook together and some of the caps values

All caps under 35 volts are Rubycon except the ones on the inverter boards

YXG replaced FC

470 uf @ 25 volts ESR reading .03 cap reading 478 uf
470 uf @ 25 volts ESR reading .04 cap reading 477 uf
470 uf @ 25 volts ESR reading .03 cap reading 477 uf
470 uf @ 25 volts ESR reading .05 cap reading 477 uf

YXG replaced FC


1200 uf @ 35 volts ESR reading .03 cap reading 1056 uf
1200 uf @ 35 volts ESR reading .03 cap reading 1059 uf
1200 uf @ 35 volts ESR reading .03 cap reading 1040 uf

YXG replaced FC


1000 uf @ 10 volts ESR reading .04 cap reading 1123 uf
1000 uf @ 10 volts ESR reading .04 cap reading 1113 uf
1000 uf @ 10 volts ESR reading .04 cap reading 1111 uf

YXF replaced FC


100 uf @ 35 volts ESR reading .11 cap reading 87 uf
100 uf @ 35 volts ESR reading .13 cap reading 87 uf
100 uf @ 35 volts ESR reading .11 cap reading 86 uf
100 uf @ 35 volts ESR reading .12 cap reading 87 uf

YXF replaced FC


220 uf @ volts ESR reading .12 cap reading 214 uf

Rubycon 85 C FRS

100 uf @ 450 ESR reading .91 cap reading 88 uf
100 uf @ 450 ESR reading .91 cap reading 88 uf
100 uf @ 450 ESR reading .85 cap reading 89 uf
100 uf @ 450 ESR reading .95 cap reading 88 uf

____________________________________________________________
These cap where on the inverter board brand Samwub LT VOA Pet

replaced FR


470 uf @ 35 volts ESR reading .03 cap reading 440 uf
470 uf @ 35 volts ESR reading .03 cap reading 438 uf
470 uf @ 35 volts ESR reading .02 cap reading 436 uf
470 uf @ 35 volts ESR reading .02 cap reading 436 uf
____________________________________________________________

One thing I notice now that I recap this set when you turn ON the power to the set it take about 5 seconds for the sound to come on an .5 second more for the channel to show on screen then .5 second for the back light to come on to see the picture on the set

It use to this when it was new

What was happing was that would take 6 to 10 second for sound and picture to come on together

The set has been on from 12:00 pm to 7:00 pm and work very good now

[sam_sam_sam]

Re: Philps LCD TV Some time no back light

Replaced with Nichicon LS

All four new caps
100 uf @ 450 ESR reading .71 cap reading 100 uf



Rubycon 85 C FRS

100 uf @ 450 ESR reading .91 cap reading 88 uf
100 uf @ 450 ESR reading .91 cap reading 88 uf
100 uf @ 450 ESR reading .85 cap reading 89 uf
100 uf @ 450 ESR reading .95 cap reading 88 uf

YXF replaced FC


100 uf @ 35 volts ESR reading .11 cap reading 87 uf
100 uf @ 35 volts ESR reading .13 cap reading 87 uf
100 uf @ 35 volts ESR reading .11 cap reading 86 uf
100 uf @ 35 volts ESR reading .12 cap reading 87 uf


Dose any one think that these cap listed here could have been causing the problem that i was having wit this TV set

[sam_sam_sam]

Re: Philps LCD TV Some time no back light

One thing I almost for got to say

I found on both the inverter board where the transformer pins go to the board the solider joints look very ? able there was a lot of flux came out from the pins so I re-flow all pin's joints

[sam_sam_sam]

Re: Philps LCD TV Some time no back light

The other night I turn on this TV and all I got was sound turn back off waited about 30 seconds and turn back on and work again

Once in a while when you turn this TV it just has one color on the screen if you turn it off and wait 30 second and turn it back on every is OK again

Up-Date

From the time I recap this set until now

This set come on every time I turn it on

On another note about a year ago just before I found this forum which by the way where I have learn alot
I found a 42 " LCD TV set in the trash pile at the street when I open it I found two caps that pop there tops replaced both of them and it still works very good today

I want to thank all of the people on this forum that day in and day out help people like me Thank You

[sam_sam_sam]

Re: Philps LCD TV Some time no back light

Up-Date to this repair of this Model # is 42PFL5332D37

I still have the same problem

The sound come ON but the back lights do not come ON if you turn the set off for 30 seconds and turn it back ON it works the way it should this happen about a two month ago then about a week ago or so the same thing happen again

Dose any one have any idea what is going on with this set

[sam_sam_sam]

Re: Philps LCD TV Some time no back light

Dose anyone have any idea what is happening to this set

[anno]

Re: Philps LCD TV Some time no back light

check the voltage to the inverter board. when the backlight is off , is there voltage (most of time 24 volt)? check if there is a 'inverter on signal' (inv_on). maybe there is a bad ccfl lamp.

[budm]

Re: Philps LCD TV Some time no back light

I see the list of caps, so the caps on the Master and Slave boards are replaced? DO AS anno suggested to see if you have those two signals when you do not have backlights.
Post closed up pictures of the inverter boards if you are not sure which pins to use for tesing.

[sam_sam_sam]

Re: Philps LCD TV Some time no back light

Thanks for the info