One of the most common (and inconvenient) problems with the Mitsubishi Mirage is when it has no heat coming from the heater. Not having a functioning heater makes driving much less comfortable, and can be a sign of certain issues. At the simplest level, there are two main reasons why the heater is not working. If it’s not coming on at all, it’s usually either the blower motor or some other wiring issue. If the heat is blowing, but blowing cold, it has something to do with the coolant getting to the heater core, or the heater core itself.