The coolant level warning light will appear on your dashboard when your engine is too hot. This is to inform you that your engine needs to cool down and is at risk of overheating. Below we look at why this may occur and the steps you may need to take.
Why is My Coolant Level Warning Light On?
Combustion engines in cars are driven with a series of controlled explosions that generate huge amounts of heat. Because of this, engines are required to have a variety of passages and a pump that constantly circulates coolant throughout the engine to maintain a safe temperature. The computer in your car is always monitoring the coolant temperature and fluid levels to make sure that the correct temperature is always maintained. When the coolant temperature is too hot, the warning light will be displayed on the dashboard.
What is the Coolant Level Warning Light?
The coolant level warning light usually means that your car is running low on engine coolant, and your engine may be potentially at risk of overheating. A low coolant level usually means that there is a leak present causing it to escape from the engine, which will need to be checked by a mechanic as soon as possible otherwise the problem is only going to occur again.
What Does it Mean When the Coolant Level Warning Light is Flashing?
If the engine coolant light is flashing, this could indicate a cooling system fault. This could mean that there is a sensor fault or a serious problem where the coolant is no longer circulating around the engine. This problem is usually caused by a faulty coolant pump, which will need to be replaced to avoid the engine overheating.
How Does the Coolant Level Warning Light Work?
The coolant level warning light will show up on your dashboard when your car is running low on coolant. Most of the time, this will occur due to a leak that is causing the coolant to escape from the engine. With less coolant circulating around the engine, this increases the risk of your engine seriously overheating while you are driving, which can lead to significant damage. If you notice this light, you may need to book a coolant change or have your car serviced.
What are the Common Reasons the Coolant Level Warning Light Will Come On?
Leaks
Low coolant levels in your car are most commonly caused by leaks. These can occur either in the coolant reservoir or somewhere in the lines. Coolant leaks can often be a serious issue as they are not always easy to diagnose and can be difficult to fix. Since the coolant travels around the engine, there are various places where it might leak out including the radiator, water pump, and hoses.
Sensor Faults
If you have checked your coolant level after the light has come on and it seems to have the right amount in the reservoir, the issue might be due to a sensor malfunction. Many coolant reservoirs have a floating sensor that triggers the light to be turned on once the coolant drops below a certain level. This is something that you will need to have checked and corrected by a professional. A sensor replacement will usually solve the issue.
Pump Issues
Sometimes, the light illuminated on the dashboard might be a sign of a more serious problem, such as coolant pump failure.
Is it Dangerous to Drive with the Coolant Levels Warning Light On?
Your car will still be drivable when the coolant temperature or level warning light is on. However, driving your car can risk significant damage to the engine if it is overheating. If the coolant level warning light comes on when you are driving, the best thing to do is pull over as soon as possible in a safe place. You should then allow the engine to cool down for at least thirty minutes before attempting to go near the engine. This is because the engine will be very hot at this point and removing the radiator cap could risk burning yourself as the coolant starts boiling.
Once the engine has cooled down, check the overall coolant fluid level. You can add some water temporarily to make it safer to drive the car to a garage and have it checked out. Another trick is to combine a 50/50 mixture of water and antifreeze, which can be put in the coolant reservoir to cool the engine down while you drive to a garage to have the problem checked out by a professional.
How Much Does it Cost to Fix the Coolant Levels Warning Light?
How much it will cost to fix the coolant warning light will depend on the problem. In some cases, a coolant change might be all that you need to fix the problem. However, if you have been driving with the coolant light on, you may have engine damage which can be expensive to repair. Other issues like damage to the sensor, coolant leaks, and damage to the coolant pump will vary in price depending on the exact issue. The best thing to do is book a diagnostics test for your car so that you can find out what has gone wrong and how much you can expect to pay to have it repaired.
Will My Car Fail its MOT if the Coolant Levels Warning Light is On?
You may be surprised to hear that leaks of engine coolant are not always considered to be reasons for the MOT test to fail. However, you may get an advisory on your test if your vehicle is leaking coolant fluid. The amount of fluid that is being leaked will also determine whether your car passes or fails. DVSA guidelines state that the car will only fail an MOT if the coolant leak is severe enough to create a pool that is more than 75mm in diameter on the floor within five minutes. Serious engine overheating and malfunctions of the coolant pump, however, are likely to cause your car to fail the MOT test.
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