OJ spilt on Dell Inspiron E1405 laptop how do I replace start on?

I have taken the keyboard off and have found replacement part for that. Can get into computer if I take the motherboard battery out and replace it then plug in computer. I also am able to do a restart when shutting down. Everything as far as OS is running fine when up. lights on strip where on is are working, but on does not work. Oh yeah, battery pack works, but won't all me to start using method above if battery in. What to do. Laptop is only a year old.