- No heat comes out.
- Heat is always on and you can't turn it down.
- Heater operates erratically, putting out more or less heat without any control changes.
- Coolant leaks.
- Low coolant level.
- Higher-than-normal temperature gauge readings (from loss of coolant)
How do you test a heater control valve?
- Bring the engine up to operating temperature and switch the heater to the hottest setting.
- Check the temperature of the valve's outlet hose (between the valve and the heater core)—it should feel nearly as hot as the valve's inlet hose.
What happens when the heater control valve goes bad?
A faulty heater control valve may not be able to properly control coolant flow to the heater, which may result in problems with operating the heater. The
heater may produce hot air
, but only at certain times, such as at idle, and the hot air may come and go.
What controls the heater control valve?
The heater control valve (sometimes called the hot water valve) is used to control the rate at which coolant flows through
the heater core
. The valve is located on the heater inlet hose. Manually operated systems may use a cable, a vacuum motor or an electric solenoid to operate the valve.
How much is a heater control valve?
The average cost for a Heater Control Valve Replacement is
between $180 and $202
but can vary from car to car.
Can you drive with a bad heater control valve?
Because your heater control valve is part of your car's climate control system, your ability to keep your windows clear and yourself warm can be affected. If you can't see out or are too cold to drive properly, a bad heater control valve could potentially cause a
loss of
control and a crash.
Can you test a heater control valve?
How to test a heater control valve.
Adjust the heat to the full on position
with the engine at operating temperature. Then check the temperature of the hose on the inlet and outlet sides of the heater control valve. The inlet and outlet hoses should be the same temperature.
Can you bypass heater control valve?
Some people opt to bypass a faulty heater control valve rather than replace it. Unfortunately, bypassing the valve can cause several issues. Bypassing the heater control valve
is not a good idea
because the modification compromises the cooling system's integrity.
How do I know if my climate control module is bad?
- Inconsistent cooling. Because the AC control module controls and regulates all of the functions of the system, you may begin to notice cooling inconsistencies when there is a problem. …
- Out-of-date software updates. …
- Uneven air distribution.
Why is my car blowing cold air when the heater is on?
Problems with the vehicle's heating system can be either no air or only cold air coming out of the heating system. A car heating system blowing cold air can be due to
a faulty thermostat, low coolant fluid level
, malfunctioning heater core, a leaking cooling system, or problems with heating controls and blend door.
How can you tell if you have a bad heater core?
- Fog Inside Your Car. Two things could be going on if you have fog inside your car. …
- Sweet Smells in the Car. The sweet smell in your car might not be your perfume or the donuts you're taking to work. …
- Constant Engine Coolant Loss. …
- Cold Air in the Cabin. …
- Cold Cabin/Hot Engine.
Can a thermostat cause no heat?
Thermostat. A faulty thermostat could be behind your car's heater not working. If it isn't opening up to let the coolant flow through it,
the core can't produce heat
. Thermostats can also get stuck open causing the engine's temperature to stay low.
How expensive is it to replace a heater core?
Replacing the heater core can be an expensive job, and usually costs
between $564 – $927 for parts and labor
. The parts aren't particularly expensive, normally costing $80 – $234, but the location of the heater core means that labor costs tend to be quite high.
How do you fix a heater control circuit?
To fix this, check for
any blown fuses and disconnect the oxygen sensor connector
. Using the voltmeter, with the engine off, check whether there's a 12V fused battery feed to the heater element. If you see no voltage, then repair the short or open in the B+ feed circuit.
Why does the heat in my car only work when the car is moving?
When your vehicle is in motion and driving down the road, then
engine coolant temperature tends to get hotter on the engine before it gets
to the radiator, so the heater will naturally heat up more when driving around.
Can you still drive with bad heater core?
If you have a bad heater core, you should bring your car in for repairs right away. Driving with a faulty heater
core can be risky
, as it can lead to overheating and extensive engine damage. Even a clogged heater core can prevent proper coolant circulation, causing your engine to run hot.
