Flashin Alien logo and HDD error in diagnostics

I purchased my M11x R1 in December'2010. It has been running absolutely fine until now. Now every time i turn on my laptop the power button(alien logo) starts flashing and i get a critically low battery warnign even if my system is plugged in to the adapter. This causes my system to keep shutting off abruptly after 2-5 mins. Also on running the diagnostics i got a battery error(0146).

After contacting dell i've had my motherboard replaced twice and my HDD replaced once( however the new HDD that was sent was also faulty and i couldnt even load windows into is as my system kept hanging, not to mention the fact that it was making loud vibration noises.)

Dell has made me run diagnostics and have tried to debug my system many times but still havent been able to find the root cause to this issue.

Any support would be appreciated.