Philips 32PFL6606T 32" LED no back light

[shepp]

Re: Philips 32PFL6606T 32" LED no back light

managed it, i pulled the board forward and did it

1. 3.3
2. 94mV
3. 22mV
4. 24mV

and more or less nothing on the others

[shepp]

Re: Philips 32PFL6606T 32" LED no back light

sorry

1. 3.3 vsb = 3.3
2. stanby = 94mV
3.4.8.14 GND 1
5.6. 12V3 = 12v
7.VSND = 24v
9. BL_on = 3.1
10. BL_Dim = 0
11. BL_CTRL = 0
12. POK = 0
13. 24V = 24v

[multimeter]

Re: Philips 32PFL6606T 32" LED no back light

sorry

1. 3.3 vsb = 3.3
2. stanby = 94mV
3.4.8.14 GND 1
5.6. 12V3 = 12v
7.VSND = 24v
9. BL_on = 3.1
10. BL_Dim = 0
11. BL_CTRL = 0
12. POK = 0
13. 24V = 24v

and that is with power on?

[shepp]

Re: Philips 32PFL6606T 32" LED no back light

yes

should there be bl_ctrl voltage?

[multimeter]

Re: Philips 32PFL6606T 32" LED no back light

the bl_on signal i think should jump to the bl_ctrl pin,to activate the back lights,that control should come from the main board,have you a picture of the main board ,one of the connectors ,and an overall pic

[shepp]

Re: Philips 32PFL6606T 32" LED no back light

do the 2 caps look dodgy to you? if thats what they are the 2 silver ones numbers : 1D VGA 220 35V they look a little dodgy to me but i dont know what they do or if they go like that with use on the last picture

[shepp]

Re: Philips 32PFL6606T 32" LED no back light

if i were to bridge the BL_on with BL_CTRL should the back light light up? or is this not a good idea?

[multimeter]

Re: Philips 32PFL6606T 32" LED no back light

those caps look fine

[multimeter]

Re: Philips 32PFL6606T 32" LED no back light

if i were to bridge the BL_on with BL_CTRL should the back light light up? or is this not a good idea?

all depends on the circuit,id only try it with the mainboard disconnected

[shepp]

Re: Philips 32PFL6606T 32" LED no back light

ive got 3.2 v on bl_dim now

and 1.5 V on Bl_ctrl

[tom66]

Re: Philips 32PFL6606T 32" LED no back light

ive got 3.2 v on bl_dim now

and 1.5 V on Bl_ctrl

Does this change when turning the TV on and off?

Where is the output to the LED backlights?

[shepp]

Re: Philips 32PFL6606T 32" LED no back light

yes they become 0v its on the other connector on the power board previously posted

i did notice when i tried the service button options to see if it was a setting the red stanby light flashed slowly twice then flashed 7 times after that, does that mean the tv was in service mode? and that was the fault code?

[tom66]

Re: Philips 32PFL6606T 32" LED no back light

yes they become 0v its on the other connector on the power board previously posted

i did notice when i tried the service button options to see if it was a setting the red stanby light flashed slowly twice then flashed 7 times after that, does that mean the tv was in service mode? and that was the fault code?

No voltage going to LEDs? I would start here then. Check diodes for shorts on the LED output.

[shepp]

Re: Philips 32PFL6606T 32" LED no back light

done that already, first thing i did, then had a look around for fuses but the ones i found were ok they are marked FB and then the number but not sure if they are fuses but they measured 0ohms, they look similar to diodes but with no markings on and all black, theres about 6 in total scattered around the board, if you look on the pictures of the power board you can see them under the main board connector (3 of them)

post #13 picture 4 you can see one there FB904

[tom66]

Re: Philips 32PFL6606T 32" LED no back light

done that already, first thing i did, then had a look around for fuses but the ones i found were ok they are marked FB and then the number but not sure if they are fuses but they measured 0ohms, they look similar to diodes but with no markings on and all black, theres about 6 in total scattered around the board, if you look on the pictures of the power board you can see them under the main board connector (3 of them)

post #13 picture 4 you can see one there FB904

Those are ferrite beads.

Check all the diodes near the connector, see if any are short.

[shepp]

Re: Philips 32PFL6606T 32" LED no back light

they are all 0.4 v and OL so all good, and just rechecked all the other diodes and they are all ok

[tom66]

Re: Philips 32PFL6606T 32" LED no back light

they are all 0.4 v and OL so all good, and just rechecked all the other diodes and they are all ok

On PSU output too?

Okay, is there a startup cap?

[shepp]

Re: Philips 32PFL6606T 32" LED no back light

i have just checked the caps on the right hand side and one only measured 2nF! with a resistance of about 600ohms thats in circuit but still didnt expect to see that, the others were Mohms and near correct values for uf, yes there looks to be a main start up cap on the left near the white 105K poly Cap ill check that now, but not sure my meter will be able to do that size

[multimeter]

Re: Philips 32PFL6606T 32" LED no back light

some power supplys will come on with out a load,it means you could test the led backlights are working,by jumping the standby voltage to the ps on with a resistor,then jump the pins for bl_on to bl_ctrl they should fire up if the led network is working,but disconnect the main board,t con etc first,it should rule out if the backlights are working or not,its either a main board,transformer,or backlight led fail issue

[shepp]

Re: Philips 32PFL6606T 32" LED no back light

that one measures 70uf and Mohms resistance the long cap with the grey plastic on the end