XPS M1730, orange battery light

Hi,

I just got my hands on a 2007 XPS M1730 for pennies on the dollar and trying to bring it back to life. Right now it won’t power on and has the blinking orange and blue battery light. The power supply with turn blue when first plugged in but when you try to turn it on just goes out. Battery has full green bars other then one. I’ve seen a lot of post for this problem but nothing up to date so wanted to see if there was any new knowledge for this laptop. I’ve seen that it could be the power supply, battery, or motherboard but is there a way to fully check what part it is so I’m not just wasting money and throwing parts at it?

Thanks nick