mine is on all the time but theres a piece of black tape over it, same thing with the airbag light.

 

Most likely low brake fluid level. I had the same symptom while stepping on gas hard

 

actually, i don't think this is so ridiculous. i was going to suggest this as well (or maybe we're both crazy ). mine was loose and bumps in the road would make it jiggle on or off (the contacts were pretty bad too)

 

the "i" is telling you to check the instruments, it is linked to the warning lights on the dash. Given your description, the most likely cause is low brake fluid level, check it. The level should be visible through the side of the reservoir, while you are at it check the condition of the fluid. Oil level is only going to turn on the light if it is low when you start the car, at which point the light will stay on untill you turn the car off. Somrtimes the "i" will be on with no apparent cause, if this is the case, make sure that all the warning lamps are illuminated with the key on and engine off, check the owner's manual and compare what you see on the dash with the diagrams in the manual. A burned out ABS or airbag warning lamp bulb, for example, will turn on the central informer and set a code in its respective control unit.