Warning light on e46 that appears when the heater is used

[solidlad84]

Hi all. Got a bit of a confusing problem going on at the moment with my 330 coupe. For about 2 weeks now every time its a cold night and I turn my heaters on in the car within 30 seconds a warning light appears on the left side of the dash. This light only comes on when the heaters are on and also turns off within 30 seconds of the heaters being turned off. Does anyone have any idea what this could be?

Thanks in advance for any help

[john_p]

Low coolant, probably.

When you turn the heaters on valves open and some of the coolant goes through the cabin heater. It might just be running low or you might have a leak.

Check the coolant (when the engine is cold!) and see if the floaty-dipsick thing is at the right level. Don't overfill it !