Should You Keep Driving If Your Engine Temperature Warning Light is On?

What the coolant temperature warning light means

On engine startup, the warning light will illuminate for a second or two to check the bulb and should then go out. If the warning light is illuminated even after startup, it indicates that the car’s computer has detected an issue within the system. The most common reasons for the warning light to displayed are the temperature or fluid level of the coolant.

If you are driving when this warning light goes on, pull over safely as soon as possible and shut off the engine to let everything cool down. Let the engine cool down for at least 30 minutes before attempting to remove the radiator cap and remember to use a thick rag to protect your hand when you do so. Never attempt to remove the radiator cap off of a hot engine. The radiator cap is designed to pressurize the system so that the water doesn’t boil as easily. Removing the cap from a hot engine will cause the coolant to start boiling and the steam will most likely burn you. Once the engine has cooled, check the overall fluid level of the coolant. If the level is low, you can add just water temporarily so that you can drive somewhere to get the car checked out.

Keep in mind that a low coolant level means a leak is present which needs to be remedied at the earliest. Otherwise, your car will eventually be low on coolant again and run the risk of the engine getting overheated. The car’s computer will typically save a code when faced with any issues so having a scan tool hooked up to the car can be of immense help in identifying the problem.

Will my Car Fail its MOT if the Engine Temperature Warning Light is On?

Given the problems an engine temperature warning light indicates, it makes sense that a car will not pass its MOT if the light is on. Therefore, you should have it fixed before going for the MOT, as it’s a recognised criterion for failure.


What Should You Do When the Temperature Warning Light Comes on?

The warning light flashes for a second or two when the engine starts. If it stays on, there’s must be something wrong with the coolant.

You should never dare to continue driving when the light is on. Pull over as soon as possible and shut the engine off. Wait for at last 30 minutes for the engine to cool down. Wear a thick glove or wrap the hand with a thick towel or a piece of rag and remove the radiator cap to check the coolant level. Never do this when the engine is still hot because the steam coming out of it can burn you.

If the fluid level is low, add plain water and drive to a nearby repair shop to check everything thoroughly. Remember that it’s just a temporary solution. Low level of coolant means there a leak somewhere, which is needed to be addressed quickly.

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On the other hand, if the car gets overheated despite no leakage or low coolant level, you should not drive it again before taking it to an auto servicing center.

Coolant temp light

The coolant temp light, which looks like a power pole in waves, will let you know if the coolant has exceeded its operating temperature, which is a sign of overheating. You will want to pull over immediately and look for coolant leaks.

Types of engine temperature warning light on car

Depending on the type of warning light your vehicle is throwing could determine how far along the heating system has been impacted. These warning lights are defined as follows:

  • You may have a temperature gauge on your dashboard, normally its nearest to the speedometer. This will have an indication of where your vehicle’s temperature stands displayed by the position of the needle
  • A red, or yellow, light may illuminate on your dashboard. Depending on the situation the light may blink when the engine temperature is too high. Indicating for you to turn off the engine.
  • If your car has an onboard messaging system you will see an “engine overheating” message on the driver’s information display. This may also be shown as an alternating icon of a radiator fan and then back to the image.

Regardless of what indication is being displayed on your vehicle all of the information is being broadcasted from a combination of sensors found in the powertrain computer and temperature gauge. When these lights illuminate shutting off your car is imperative to sustaining the life of your engine, since one degree too hot could lead to a malfunction inside the vehicle.

Engine Temperature Warning Light car on Cold Days

When you start your vehicle on a cold day you may notice the temperature gauge sitting below the beginning of the temperature limit. If your vehicle has a temperature overheat light installed in the dashboard it may illuminate for about 1 or 2 seconds. As the engine warms up the needle will level out and slowly rise as the engine warms up. This way it’s reflecting the accurate temperature being thrown by the engine.

How Do I Fix an Engine Temperature Warning light?

When it comes to fixing a temperature warning light you are pretty limited with basic troubleshooting, though if you catch the event early enough some preventions may save your engine. One of the easiest things to try to do would be to turn on the heat in your vehicle to full blast, though it may sound counterintuitive to do so there is a good reason to do this. When you turn on the heater you are reducing the strain being put on the engine from the massive amounts of heat it’s been piling on. Essentially you are alleviating the heat from the engine and allowing it to circulate which allows for cool air to be passed through. This also will cause the coolant system to circulate all of the remining coolant through the system. Depending on the severity of the heat already given off from your vehicle you might find that this works or doesn’t work at all.

Another thing to try would be to pull your vehicle over to the side of the road and leave your car in park. Leaving the hood closed for at least 20 to 30 minutes after coming to a full stop with all the vehicles power off. If you attempt to open the hood immediately after stopping your vehicle you are putting yourself and those around you in danger since the cooled pressure from the surrounding air will react with the heat from the engine. This temperature differentiation could cause a radiator to rupture and blow scalding steam everywhere, or you may have developed a bad radiator cap and it’s forced off of the coolant tank splashing extremely hot coolant all over the place. Contact with either of those could result in third degree burns at the bare minimum. Contact a mechanic before doing

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ABS light

ABS stands for anti-lock braking system. If the right reading ABS comes on professional diagnostics will need to be completed using a scanning tool.

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Schedule Warning Light is on Inspection

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Check Engine

The check engine light, which looks like an engine

The check engine light, which looks like an engine icon or the phrase “CHECK ENGINE,” is a component of your vehicle’s diagnostic system. This computerized system produces Diagnostic Trouble Codes (DTCs) that automotive service professionals can decipher to get to the bottom of the problem. Typically, issues that trigger the check engine light are related to emissions systems. These aren’t usually emergency situations, but they do need to be resolved by a trained technician as soon as possible.


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