Mulja tv repair portal

Equipment Repairs => LCD TV forum => Topic started by: kennyc on September 08, 2019,08:50:43

Title: jvc LT40C755A BACKLIGHTS
Post by: kennyc on September 08, 2019,08:50:43
Hi Guys ,got this TV in for repair . Only see the JVC emblem for a second then screen goes blank . Suspected backlight LEDs and took screen apart . To my surprise there were no visible LEDs . It has a Vestel 17IPS71 power supply.  Only lights are on a board on the right hand side as you look at the TV from the back . It seems to be one vertical strip . Have left pics if you want to see . Does anybody know how to check this strip.? thanks
Title: Re: jvc LT40C755A BACKLIGHTS
Post by: astracat on September 08, 2019,09:49:47
hiya
whats at the other side of that metal strip ? as need to actually see light strip
regards
astracat
Title: Re: jvc LT40C755A BACKLIGHTS
Post by: kennyc on September 08, 2019,12:43:55
Hi there ,if you look at the bottom of pic 3 you can see the LEDs. The rest of the metal board just seems to be a heat sink. It is the same on both sides. There are about 20 small LEDs on the strip  . Their is a plug at the bottom of the LEDs that is attatched to the power supply. If you look at pic 2 you can see the strip of LEDs with the small plug on the rightt that gets attatched to the power supply. Have never seen this LED strip in any other TV
Title: Re: jvc LT40C755A BACKLIGHTS
Post by: downunder on September 09, 2019,05:50:20

Hi Kenny, Looks like it's edge lit from the bottom - getting common now. if you have a LED checker, it looks like you have enough contact at the ends of the LEDs to be able to test them. They're usually in groups of ten or so, fed from the connector end, but the fault often lies in the encapsulated tracks on the strip. We've been able to get some of these strips (Minus the Al heatsink) from China (Aliexpress) for Sony's for instance, but you'd have to check to see if yours are available.          Bruce
Title: Re: jvc LT40C755A BACKLIGHTS
Post by: kennyc on September 14, 2019,12:49:21
Hi Bruce ,have ordered a new LED strip from Ali Express . Seem quite reasonably priced only thing is delivery is between 20 and 40 days . Will let you know what happens . Thanks for your help
Title: Re: jvc LT40C755A BACKLIGHTS
Post by: downunder on September 15, 2019,02:19:04

Yeah, getting stuff from China is a PITA. It takes so long. I have an LG TV in bits at the moment waiting on strips. I worried about the screen sitting around unprotected. And when they say 'free delivery' you can be sure it's sent via the cheapest and slowest way possible.             Bruce
Title: Re: jvc LT40C755A BACKLIGHTS
Post by: kennyc on September 19, 2019,08:35:57
Hi Bruce ,got LED strip today so thats just about 10 days to come . Fitted it and everything is fine . No screws on LED strip just a sticky strip that you peel off and fit .All seems quite simple just the usual problem of not cracking the screen. I would use AliExpress again they even sent me an email saying that the parcel had been delivered to my local post office just before it arrived. LED comes well packed in a solid tube . Whole thing worked out at $15 thats about £12 with a $3 first order discount . Saw them on EBay for around £40 so its a big saving and like I say easy to fit. Cheers and thanks for your help