LG 55lk530-uc ford not turn on.

[capwizard]

Mistyping title does to ford...reality is cellphone or Google has changed automatically for me. Anyway. I did not pay attention to it.

LG 55lk530-uc has red light and 3.3v STB voltage. Push power butten. Tv has 24v and inv-on(3.3v). But no ccfl backlight. Before I open the backlight how can I know it is the ccfl backlight problem. Can I test 55 inch tv only has two connectors with my cfl tester. I mean the cheap blue ccfl tester can drive all the ccfl lamps? And I couldn't find the tester.
Ps. both ccfl driver board have no short.

[CapLeaker]

Re: LG 55lk530-uc ford not turn on.

What does the INV-ON pin say? If there isn't anything there, the backlights stay off. Maybe it doesn't get from the main board the command to turn on?

[capwizard]

Re: LG 55lk530-uc ford not turn on.

I did double check the pin of inverter-on..when I push power button this pin went up to 3.3v then I push butten again tv will shuts off. Inv-on became 0v.

[CapLeaker]

Re: LG 55lk530-uc ford not turn on.

...and you get nothing at all? Not even a 2 second to black? What about adim, pdim and err?

[nomoresonys]

Re: LG 55lk530-uc ford not turn on.

Try unplug cable from powerboard to mainboard, plug tv in turn on see if backlights come on and stay on.

[budm]

Re: LG 55lk530-uc ford not turn on.

Fuses on Both master and Slave Inverter boards are good?
You have Master/Slave inverter driver boards setup for push-pull lamps driving, so if Master is good but the Slave is bad then you will see backlights on the side where the Master inverter is come on up to the middle Horizontal of the screen for seconds.
If the Master inverter driver circuit is good but output circuit is bad but the Slave inveter board is good then you will see the other half of the screen light up for seconds.
So we need to know for sure if you even see 3-seconds to black or not and if the Dim and Error signals are OK or not.
See page 42 for the topology being used.

[capwizard]

Re: LG 55lk530-uc ford not turn on.

...and you get nothing at all? Not even a 2 second to black? What about adim, pdim and err?

A-DIM, P-DIM #1 those make me confused, is that means Digital dimming and analog dimming. Why do they use this letter P for P-DIM #1 ?

I will test later and let you know.

[capwizard]

Re: LG 55lk530-uc ford not turn on.

Fuses on Both master and Slave Inverter boards are good?
You have Master/Slave inverter driver boards setup for push-pull lamps driving, so if Master is good but the Slave is bad then you will see backlights on the side where the Master inverter is come on up to the middle Horizontal of the screen for seconds.
If the Master inverter driver circuit is good but output circuit is bad but the Slave inveter board is good then you will see the other half of the screen light up for seconds.
So we need to know for sure if you even see 3-seconds to black or not and if the Dim and Error signals are OK or not.
See page 42 for the topology being used.

I did check the fuses and bridged MOSFETs they are OK.

can I test this tv backlight with CCFL tester?

why i keep on asking this because the CCFL tester has been disassembled for scientific purpose research.

[budm]

Re: LG 55lk530-uc ford not turn on.

A-DIM, P-DIM #1 those make me confused, is that means Digital dimming and analog dimming. Why do they use this letter P for P-DIM #1 ?

I will test later and let you know.

A-DIM = Analog dimming control.
P - DIM = PWM dimming control.
It will use one or the other but not both.