2003 Rover 25 Light Appears

Hi, on my car a orange warning light appears when im driving my car, its not the engine management light, the picture of this light is a circle with a explanation mark inside and out of the circle there are tiny lines sticking out. When this light comes on the fan also comes on, once i switch the car off and leave it for about 2 minutes and start it again the light goes and the fan turns off, but then after a while it comes back on, sometimes it doesnt come on for days and sometimes it comes on 3 times a day. Could you please explain what the light means, I have attached a picture of what the warning light looks like

Thank you