I have noticed recently that when I'm at a stop light or sitting at idle the temp of the heater cools off. I checked the coolant level in the reserve and it is low and needs refilling. Can I simply add more antifreeze to the reserve tank or do I need to bleed the system or take it to the dealer to do this?

 

Is it bone dry???? To answer your question though, yes, you can add coolant but be sure it's the correct type (blue from Mini or Zerox Z05). Try filling it to level and recheck in a day. If you are losing coolant still you may have a thermostat/housing leaking. Have dealer check for you. When mine was leaking I couldn't find a puddle but it was accumulating under the engine pan. It's about $450 if they do it.