Please help me because my problem is no light and LCD unit is k850i

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Dear User
You have to just reset your Phone. Still problem exist , you may need to check your Connectors to display and to Key pad....
Hope this helps ....Let me know if you need further assistance....Thanks for Connecting FixYa....

Try reading K850i Firmware Overview.. There are some issues with firmware. Such as random reboots and BROD (Blue Ring of Death) i was recently victimized by this BROD. 037 firmware is the most stable firmware so far.. i would advise you also to downgrade your firmware first until SE releases a new and more stable firmware..

its usually happen at k850i.the problem actually from display light on lcd are not lighting. if you have experience in phone you can make a jumper wire to reconnect light line between lcd and PCB(engine).but usually the fastest way are change the lcd phone.simple but need money.may it help.

take it to a phone repair shop is best advise i can give as it seems there is more wrong than just the lcd

So if the K850i LCD won't light either the backlight or the LCD itself has gone bad. It is a fairly easy procedure to replace yourself and you can pick up the LCD from ebay for 15-25 dollars.

Here is a guide for it and it also includes links to buy a replacement display:

Sony K850i LCD Display Screen Replacement

you reprogram your phone

Replace the LCD....

Hi. The backlight is part if the LCD screen so replacing this part should solve the problem. Have a look here for parts and a guide http://www.formymobile.co.uk/Dismantle/k850idisassembly.htm

try replacing the lcd or the cable on the phne to correct this issue.....take the phone to a mobile service center and have this done.

erwin - take the phone and have the firmware reflash on the phone and if that does not work then have the lcd replaced in the phone.

guest - replaced the phne lcd

darkside_ody - changed the lcd or the mainboard on the phone