What Does A/T Oil Temp Mean? Here’s Everything You Need To Know

If you are driving and your A/T Oil Temp light starts flashing, it can be alarming and worrying to you, especially if you don’t know what it means. This article will provide you with an overview of what a flashing A/T Oil Temp light means, what steps you can take to avoid it coming on, and what actions you need to take to turn it off.

What Does AT Oil Temp Mean?

A/T or A/T Oil Temp is short for an Automatic Transmission Oil Temperature control system. Your engine’s transmission can only handle so much heat, so it is important that you can manage situations where the temperatures get too high.

Most vehicles can cope with temperatures of around 200F, but if the temperatures within your transmission get too hot, it can have serious impacts on your car’s engine.

Dashboard dials are illuminated at night in an automobile.

Your A/T Oil Temp light will start flashing if the temperature goes above your car’s maximum, and it is important to take some form of action to cool it down before any extra damage is caused to your vehicle.

Can You Drive With The A/T Oil Temp Light On?

You can continue driving if your A/T oil temp light is on. However, you are increasing the risk of serious damage being made to your car. Even if you do decide to keep driving, you shouldn’t drive too far and you should be on the lookout for any sudden changes in the performance of your vehicle, such as it slowing down or beginning to shake.

To avoid any further damage, if you are driving and your A/T oil temp light comes on, it is advisable to pull over as quickly as it is safe to do so. You should then turn off the engine, which will allow your car, the engine, and importantly the oil within the transmission to cool down. If you have been on a long journey, or stuck in traffic for a long period of time, giving your car a well-deserved rest could be enough to fix this issue temporarily.

A woman driving a car.

If you continue to drive with an A/T oil temp light on, you run the risk of transmission failure. If your vehicle suffers transmission failure, you will be left with a very expensive repair bill, so it is often best to take action as quickly as possible to avoid further damage.

If your A/T oil temp light flashes as soon as you start your engine, this may indicate that there are issues with your automatic transmission control system. These issues can only be resolved by mechanics, and it is unlikely you will be able to resolve this issue yourself.

How Do I Fix The Oil Temperature On My Subaru?

If the problem persists after giving your car a rest, it is advisable to check your engine more thoroughly. Firstly, you could check the levels of transmission fluid within your car. If the levels of transmission fluid are too low in your car, you run the risk of the temperatures getting too high and causing damage to your engine.

💡 But beware, adding too much fluid can cause other issues, so it is best to add the additional fluid little by little to protect your engine from future damage.
A mechanic checking car transmission.

Transmission fluid needs to be changed every so often. Most transmission oils only need to be changed after 100,000 miles, which is a very large distance, meaning you shouldn’t have to change it so often. However, it can be a good idea to check the condition of your transmission fluid more often than this.

This task requires you to drain the transmission fluid and add new oil back in afterward. You can check the health of the transmission fluid by looking at the color. If you don’t want to try this task yourself, you can take seek professional help, and this is likely to cost between $80 and $250, and if done correctly, changing the transmission fluid does no harm to your vehicle.

Helpfully there are a number of instructional videos online explaining how to check if your transmission fluid needs changing, and if so, how to change the fluid. Transmission fluid in good condition should be a red or pink color whereas burnt and damaged transmission fluid is a dark brown or black color.

When checking your transmission fluid, if you find metal debris inside the fluid, this signifies that a major component has started to deteriorate, which is a major issue that should be assessed as soon as possible.

What Causes High Oil Temp?

There are a number of causes of high oil temperature, which isn’t always helpful if you are trying to work out what might be causing your A/T oil temp light to come on. Helpfully to you, there are some issues which are more common causes than others. These include as stated above low levels of transmission oil.

Transmission oil that is old can often build up and this can cause issues. This is why changing your transmission fluid when required, can stop your transmission oil temperatures from getting too high and your A/T Oil temp light from flashing. If a transmission keeps on slipping, this can also cause high oil temperatures. Similarly, a defective solenoid can cause this issue.

High transmission oil temperatures can also be caused by driving habits. If you are driving too fast in really hot weather and have a lot of stop-start driving, you could be increasing the risks of oil temperatures becoming too high, potentially causing damage to your engine.

Why Is My Oil Temp So High?

“Why is my oil temp so high?” is the first question that will come to your mind when you notice that your car’s oil temperature gauge is registering higher than usual. So, then it’s likely that you already know how detrimental high temperatures can be to your car’s motor.

Well, the first thing to know is that it’s entirely normal for oil temps to be significantly higher than water temps. Think about it: motor oil runs through a completely different cooling system than coolant.

Water flows through the engine block and cylinder head, then through a radiator (or heat exchanger for marine applications) and is cooled by airflow or water flow through the radiator. On the other hand, oil is cooled only by the surrounding metal in which it flows (the engine block).

If you’re running synthetic oil, you probably also have an external cooler somewhere in the system, but even with its help, the oil remains much hotter than water because of its location in the engine.

Moreover, If the car has a faulty thermostat, the water won’t circulate properly, automatically raising the oil temperature. Another reason may be a sticking fan clutch. That restricts airflow, which will once again raise the temperature.

Knowing this, the next question we need to ask is whether or not those higher oil temps are a cause for concern. The answer is yes — if they’re too high.

Why Is My A/T Oil Temp Light Flashing?

The A/T, or A/T Oil Temp light starts flashing or lighting up if your oil in the transmission becomes too hot for your car to handle. There are many reasons why the transmission fluid might become too hot, some are easy fixes whereas others require specialist care and attention.

Your engine can only handle so much heat. If temperatures go above the maximum your engine can handle, it can cause serious issues such as corrosion to your vehicle. If your A/T Oil Temp light starts flashing, you shouldn’t drive too far, as this increases the risk of damaging your car. This is especially true if you notice any changes in your vehicle’s performance, such as it shaking or slowing down.

If your A/T Oil Temp light is flashing, you can attempt a quick fix yourself by changing the transmission fluid yourself. If you have done this, and the A/T Oil temp continues to flash every so often, it could mean that there are other more complex issues at play.


It can be very concerning when an unknown warning light pops up on the dashboard of your vehicle. This article provides you with some useful information on what the A/T Oil Temp warning light means, and what can be done to fix it.

If you have any questions, either about what causes high A/T Oil temps or what can be done to solve them, then please comment below.

A/T Oil Temp indicates when your transmission fluid temperature gets too high, and it is important to take action. Some actions can temporarily get you through to a more long-term fix, but it is even possible to fix this issue yourself.

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About Matthew Webb

Hi, I am Matthew! I am a dedicated car nerd! During the day, I am a journalist, at night I enjoy working on my 2 project cars. I have been a car nerd all my life, and am excited to share my knowledge with you!

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