Nissan Repair: coolant smell, 2003 nissan altima, nissan altima

Question
we have a 2003 Nissan Altima 2.5S and I smell coolant, but can't find a leak
from any hoses or from the radiator.  The Service Engine Soon light is on.  What
could it be?

Answer
Hi Thomas -

This could be your heater core leaking coolant into the A/C duct of your vehicle. In more severe cases you would find a puddle of coolant under the passenger side floor mat. The heater core is a tiny radiator in the ductwork of your A/C system that channels the water from the radiator through. The fan blows the air through, thus providing occupants with warm air. Even if the heater is off, coolant can still pass through if there is a compromise in the core.

Hope this helps -
aloha
calvin