HTC Sensation keeps shutting down? Problem solved!
First of all I would like to thank all people that have replied to this specific topic, without all your help I would never come up with my solution to the problem. I won't explain how they have helped me, but at least I can tell you my phone kept shutting down about 4 or 5 times per day. I have implemented my solution a week ago and the phone hasn't shut down since.
If you open up the back cover of the Sensation and you look at the battery, you'll notice that the bottom side of the battery is slightly angled. This causes the battery to not be in full contact with the four pins that are attached to the Sensations case. If you pull the right top side of the battery a little down, you'll notice that the battery will make a better connection with the four pins. So for me the problem was solved by putting something in between the top right of the battery and the casing. I've used a business card (I knew saving those would pay of at one time) and tore of the rest that was sticking out. It's been fine ever since.
Now my explanation, although I'm far from being a electrician, is that the battery connection to the case is fine for low power situations. But as soon as more power is required by the phone, like in low connection situations, the phone will loose power and shut down. That's why ensuring that those situations do not happen or rarely happen gives some result.
Oh and two notes to HTC. One, please fire your support department, because they suck. And two, please ensure that the batteries are being held in place by your case next time you make a phone.