Had the same problem, find where the coolant topup cover is. at the bottom of this side of the rad area there is a sensor plugged in (coolant level sensor) its a bit awkward to get at, might wanna wait till engines cold. Unplug the sensor and clean the pins (i used my finger but u might wanna use somethin better) plug it back in and hey presto problem solved. Due to where the sensor is mounted dirt inevitably gets in and screws with it. If this doesn work, besides being shocked u may need a new sensor. Like i said though this solved mine and peoples other peoples problem hope it works for u