Back light is on but got black screen - Dell Inspiron 1318 Laptop Computer PC Notebook

Time to buy a new one.

Back - light problem. Check and replace damaged component/s at its back-light inverter board, or replace this board as card basis. If you wish to get some details; check the site linked here. Surf the site with patience. Pull up older posts. It will be best to replace the inverter board as card basis.
http://electronicshelponline.blogspot.com/
Some model sets; especially LED back-lighted types; the back-light inverter circuit will be part of the main power supply board [SMPS]. In such cases, the power supply board might need replacement.

no back light try using an external monitor if okay then need to replace,some screens come with back light,

Check its back-light inverter and back-light CCFL lamps.

if their is a light indicator in the front panel and with sound but the screen back light is totally black, the cause it could be the inverter board or the back light is bad.just let me know if it could help you.

There is no display in your television because the back lights of the screen is not function.The back lights have no voltage supply,maybe there's a loose connection in the connector of the back lights to the board or driver of the back lights.So its better to check the connection of the back lights and resolder the connector..Thanks..

This could be that the screen topback light or bottom back light is bad or the inverter.
the topback or bottom back light could also be seing as the flouricent of the screen that light up the screen to enable display visible.This top back light or botom back light as the name implies is positioned at the top and bottom side of the screen.It takes an expertize knowledge for one to be able to change the flouricent when comfirms bad.The same is applicable with Inverter.

It sounds like the back-light in your laptop's LCD screen has died. If you turn the laptop on, and hold the screen up to the light, you may be able to see the operating system and windows, but since the screen isn't emitting any light, it appears to be off or all black. If this is the case, you'll need to either replace the back-light, have the laptop repaired, or replace the whole thing. There's no easy fix for a dead back-light.

Could be the lamp is failing.

Assumed that LCD screen is black and what about Eye piece viewfinder? Does it show picture to you?
If LCD Screen is black, it means it has no back-light. check any button to turn back light on & off at LCD portion.
There can be an other reason of black LCD. a flexible cable which connects LCD and Camera circuits and it can be broken/ cracked/ out of order.