Embodiments of the invention provide to apparatuses and media used in drug elution studies and methods for making and using them. In a mobile unit, such as a CDMA device, a correlation pulse is generated when a transmitted code matches a stored reference code. Upon detection of a corruption by the file system, the system enhancement records information describing the nature of the corruption. The diagnosis of the tire pressure may further be based on comparing the number of wheel rotations, determined from the tire movement input, with a number of rotations determined based on the traveled distance and the predetermined radius of the tire under proper inflation.