HTC Desire 816 Problem

I have HTC Desire 816 Dual SIM phone made of 2014 July in which I have problem form last 2 days stated below:
(1) In built application "CAR" become automatically alive frequently.
(2) When prob:(1) occurs "Bluetooth" also turn on automatically.
(3) Home screen also responds to G-Censor (Potrait To Landscap also vice a versa) even after turning off the "Auto Rotate" from quick toggle.

Note:
(1) Other functionality works properly.
(2) I have tried "Factory Reset" couple of time, but not solved.
(3) When I removed the free magnetic flip cover (comes with the device), up to some extent problem get solved but not 100%.

Plese help me....Thank you...