ESP compares the driver's intended direction (by measuring steering angle) to the vehicle’s actual direction (by measuring lateral acceleration, vehicle rotation and individual road wheel speeds). Will flash with wheel spin etc. If on permanently, have vehicle check by dealer. ABS etc. might not work, but is ok to drive.
If vehicle will not drive correctly try disconnecting battery (Vauxhall Zafira suffers from ECU lock up) for five minutes to reset computer.
Can also come on,if the alternator is not charging correctly.