Sony KDL-40W2000 No Backlight (4 flashes)

[pan]

Hi

I sure I did post this prob the other day but seems to of disappeared into thin air or maybe it’s me.
Sony KDL-40W2000- no backlight
When turned on the green LED appears but then shuts down and red LED flashes 4 times stops for 2 secs then repeats and so on.
Has any of you guys had this prob ?
Pan

[sparky]

hi
looks like inverter faulty
dave

[pan]

Hi Dave


Yeah that was my thought to.
I’ve checked the transformers and smd fuses all ok.
Just thinking it could end up a backlight prob is there a test that would positively establish if it’s the inverter?
Pan

[Turnip]

Hi Pan,

There's a couple of Quuq references to inverter probs - both three flash - just a thought - Chris.

[pan]

Hi Chris,

Checked voltages again on the plug on the p/s that feeds the inverter.
Voltages are :
 
In s/by                               moments after switch on  (4 Flashes)

18v ok                                 18v  0                                     
Power on pin 3v                     Power on pin 0v
Rly on pin 3v                         Rly on pin 0v   
PFC det pin 0v                       PFC det pin 2.5v

Any thoughts.

Pan

[pan]

Hi Chris,

Sorry misinformation forget the Rly pin & p/on pin.

Pan

[Contrast John]

Hi pan
What drive IC is used on the inverter board?
Regards
John.