JVC LT-40DJ51J - Vestel 17IPS20 - LEDs very dim

[ReeceyBurger123]

Re: JVC LT-40DJ51J - Vestel 17IPS20 - LEDs very dim

Hmm yeah deffo something wrong with Psu then, normally if the Led booster mosfet or diode shorts then the Tv wont turn on at all. Sounds like the controll Ic for the mosfet has failed. It seems to be quite common on these Vestel Psu/Led drivers. I will put an ebay link to the Ic.

[tn245]

Re: JVC LT-40DJ51J - Vestel 17IPS20 - LEDs very dim

Hi ReeceyBurger. You're welcome. The videos are really helpful. As I said I tested all the LEDs and they all light up when tested in groups using the ATX psu method, which leads me to suspect the PSU. I did wonder what the backlight is set at but I'm not getting enough light output to see the screen at all so I haven't managed to check it. He said he'd turned it way up.

[ReeceyBurger123]

Re: JVC LT-40DJ51J - Vestel 17IPS20 - LEDs very dim

Hi mate, thanks for the feedback on the vid Your on the right path, the drive voltage is way too low. Possibly a shorted Led dragging down everything or maybe the drive amplifier is not turning on the mosfet enough. Silly question but what is the backlight setting at ?

[tn245]

Got this TV. Owner said the screen went dim so he turned the backlight up to counteract which worked for a while but eventually it went almost black.

The LEDs are lighting up only just, three of them not at all on one strip. Have tested all the LEDs following ReeceyBurger's excellent video instructions and they all light up nicely. Voltage to the LED string from the PSU is only ~105V. I think this should be closer to 150V for 45 LEDs am I right? So I think this is a problem with the PSU. Just wondering if any of you have come across this before and can save me some time chasing down the problem.

Thanks!