I have a Dell Inspiron N5010 Laptop with i5 Processor,But its turning on now.
When i plug in the power adapter it only flashes orange and white four times then stops. it does come on to the screen.
If I understand your question correctly, then its the third LED status indicator light, which is flashing red and white(first one is the light for power, and the second one is light for disk usage. third one is light for battery). This happens, when your bettery pack is not recognized by the laptop. In my case, shutting down the system, removing and cleaning battery contacts, and replacing the battery pack solved the problem. (Note that when your computer doesn't recognize battery pack, it will still be able to run on battery, but will not be able to charge the battery.