There is almost never a situation where you would need to take the radiator cap off of the radiator to add coolant. If the heater has stopped working in your Sonic, this process has failed in one way or another.Ĭhevy Sonic Heater Not Working: DiagnosisĪ word of caution: If there is no coolant in your overflow, you can refill it by adding more to the overflow reservoir. At this point, the blower motor blows air across the it and the newly heated air blows on to the driver and passengers. 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.Īt the simplest level possible, the heater works by passing hot coolant from the engine into a tiny radiator called the heater core. If it’s not coming on at all, it’s usually either the blower motor or some other wiring issue. Not having a functioning heater makes driving much less comfortable, and can be a sign of certain issues.Īt the simplest level, there are two main reasons why the heater is not working.
One of the most common (and inconvenient) problems with the Chevy Sonic is when it has no heat coming from the heater.
