If you stay in a region with a very cold climate, then your Honda Civic heater is a very important feature. It can be pretty inconvenient if the heater is not working, especially on a very cold day. What this means is that you and every other person in your car will be pretty uncomfortable.
Since the heater not working could be a sign of a more serious issue, you should get it fixed quickly. In this post, we show you the possible reasons why your car heater is not working. We will also show you how to fix this problem.
Faulty Honda Civic Heater: The 2 Possibilities
While several complicated issues may result in your heater not working, there are two common ones. The first is that the heater is not coming on. When this occurs, it could be that the blower motor is damaged. It could also mean that there are other underlying wiring problems.
The second common problem is that the heater is coming on but it is not producing heat. Instead of heat, the heater blows cold air. It is most likely that the core has an issue. In some cases, it could be that some coolant has gotten into the heater core.
How the Honda Civic Heater Works
Before we go ahead, we should explain how your Honda Civic heater works briefly. It is pretty simple to understand, even for a layman.
The heater passes hot coolant into a tiny radiator from the car engine. This radiator is also known as the “heater core.” When the coolant gets to the heater core, the blower motor then blows air across it. This air gets heated and then passes through the vents in the car to reach the occupants of the car.
If the air is not getting hot, then there is a problem with the process. It just means that one of the components supporting the process has failed.
Honda Civic Heater Not Working: Finding & Fixing the Problem
Now we know the most common reasons why the heater of your Honda Civic is not working. The question that begs an answer is, “why is the heater not working or why is it not producing hot air?” We will discuss a few reasons in this section.
Low coolant level
Normally, when the engine is low on coolant, it makes your engine run hotter. This is not the only problem that having low coolant may cause. It can also affect the heating system of your Civic so that it doesn’t produce enough heat. How is this possible?
To get coolant for its operation, your heater core needs sufficient line pressure. This line pressure is a result of having enough coolant in the engine. When the coolant is low, the heater core cannot get sufficient coolant.
How do you check the coolant level? It is pretty simple, look into the overflow reservoir. This reservoir is usually connected to your car’s radiator via a tube just beside the radiator cap. There should be separate lines indicating “cool cold” and “cool hot.” Remember that you should not touch the radiator cap if the car engine isn’t cold.
Bad thermostat
The job of a thermostat is to regulate temperature. This feature helps to regulate the temperature of your Honda Civic’s engine. How does it achieve this?
It allows water to get into the engine once its temperature levels are getting high. While the car is warming up, the thermostat also prevents coolant from circulating. There are times when the thermostat gets bad. When this occurs, it may remain open.
If the thermostat stays stuck this way, the coolant begins to enter the engine continuously. When this occurs, it is like your car’s heater is barely functioning. You will probably notice that the heater is functioning when the car is stationary. However, once it starts moving, the air coming from the vents gets cold.
You can easily detect if this is the cause of your problem by looking at the temperature gauge. Check to see if it is in the regular position that it should be after driving a distance. If it shows colder temperatures than usual, then you are certain that something is wrong with the thermostat.
Heater core problems
Your car’s heater core can get bad after a long period of use. This component is prone to clogging which ultimately leads to periodic failure. How does the heater core affect the working of the heater?
When the heater core is clogged, it cannot allow for the passage of coolant. If the warm coolant doesn’t pass through the core, then it cannot supply heat to the interior of the car.
Asides from clogging, your heater core can also leak. An easy way to check if the heater core is leaking is to look at the passenger floorboard. If the floorboard is wet, then you have a leaking heater core on your hands.
Connecting hose problems
Two separate hoses connect to the heater core. Both hoses take coolant to and from the core. Usually, when your car’s engine is on, both hoses should be warm to the touch. In some cars, they are even hot.
Sometimes, one hose may be warm while the other remains cold. If this occurs, then there is a possibility that your heater core has clogging issues. What if both hoses are cold? It means that the cooling system has low pressure, low fluid, or has taken in some air.
Faulty water pump
Sometimes, when you look at your temperature gauge, you will notice that the engine is hotter than usual. If the heater is up and running properly, this isn’t a cause for concern. However, if it isn’t, then the water pump may have issues.
You can quickly take the car out of gear then rev your engine a little. Once you notice that there is heat from the vents after a few seconds, the water pump is bad.
