Hitachi UZ657200 Backlight/Power Supply Issue

[Rustler77]

Hi All

I have a Hitachi UZ657200 LED TV with a backlight issue. A few minutes after powering on the screen goes black. I can see the image if I shine a light on the screen and the sound works fine. If I unplug the power for 5 minutes and then connect it again it works fine for a little while before the same thing happens. The longer I leave it unplugged the longer it will last before it happens again. The power supply PCB has an electrical hum in the highlighted area on the attached image. When the backlight fails it turners to more of a quiet crackling noise. I replaced the bridge rectifier in this area but the TV behaves exactly the same.

All help appreciated.

[diif]

Re: Hitachi UZ657200 Backlight/Power Supply Issue

It's more likely to be a failing LED, turn down the backlight and see if the TV stays on longer.

[Rustler77]

Re: Hitachi UZ657200 Backlight/Power Supply Issue

Hi diif

I plugged it back in after being disconnected for 3 hours, turned the brightness to 0 and it only lasted about 2 min. This was below average for a cold start.