How to Fix Toyota Corolla Trac Off and Check Engine Light

How to Fix Toyota Corolla Trac Off and Check Engine Light [ANSWERED]

Toyota Corollas are pretty good cars until they suddenly give you the unsightly double whammy of a Trac Off light and a check engine light turning on at the same time, just as we’ve dealt with on other people’s cars already.

Now unless you’re seasoned in the art of controlled chaos known as “drifting”, even getting the Trac Off light by itself is not good, let alone being accompanied by a potential engine hiccup.

So before you unintendedly do more than a sick “wall tap” on the next exit ramp guard rail in the rain, you better get those Trac Off and check engine lights fixed on your Corolla, and here’s how!

How do you fix the “Trac Off” and “check engine light” on a Toyota Corolla?

If your Toyota Corolla has the Trac Off and check engine light turned on, you can fix them by replacing the faulty parts that cause it, like the traction control switch, brake light switch, and shift lock solenoid.

You will be able to figure out the cause by scanning your ECU with an OBD-II reader.

One of the first things that you can do when both the Trac Off light and the check engine light (CEL) come on at the same time is to check the commonly known faulty components that can cause them to appear.

In the Toyota Corolla’s case, it can be either due to a malfunctioning traction control switch, brake light switch, or shift lock solenoid.

Apart from physically checking the condition of the components, you can have your vehicle’s computer (ECU) scanned for any error codes, as they will give you info on what’s exactly causing the Trac Off light and check engine light to appear.

It would be a different case if only the “Trac Off” light came on alone. You may have accidentally pressed the TRAC OFF button or VSC (Vehicle Stability Control) OFF button on your car.

How do you fix the "Trac Off” and "check engine light" on a Toyota Corolla

Thus, simply pushing either the “TRAC OFF” or “VSC OFF” button again will turn the traction control on and make the Trac Off light disappear.

Depending on the exact Toyota Corolla model year, the TRAC OFF or VSC OFF button may be marked with a small logo of a car skidding with the word “OFF” at the bottom.

Otherwise, both the Traction Control (TRAC) system and the Vehicle Stability Control (VSC) system will automatically turn on the next time you start the car.

What does a Trac Off light or message on a Toyota Corolla mean?

A Trac Off light or message on your Toyota Corolla can mean that there is a problem with the car’s traction control system or it has been turned off via its own button.

What does a Trac Off light or message on a Toyota Corolla mean

A “Trac Off” light or message coming up on your dashboard can mean exactly what it sounds like under normal circumstances, which is that the traction control system has been deactivated.

However, the Trac Off light serves another related purpose that you may not be aware of, which is to serve as a warning that something has gone wrong with your traction control.

In the case of the Toyota Corolla, if something goes wrong with its traction control system, then it’s usually traced to a traction control switch that has malfunctioned.

In addition, the Toyota Corolla’s traction control system can also become faulty and trigger the Trac off light due to either a bad brake light switch or a bad shift interlock solenoid.

Now the question is how can you tell if the Trac Off light simply turned on due to pressing the button or because of a fault? Well, a problem would usually be accompanied by a “check engine light” (CEL).

What does a check engine light on a Toyota Corolla mean?

A check engine light (CEL) serves to notify you of a potential issue with your car’s engine, hence suggesting to “check” your engine.

A check engine light can turn on due to a variety of reasons that may affect the engine, like transmission issues, traction control problems, and other related issues.

What does a check engine light on a Toyota Corolla mean

Despite being called the “check engine light”, there can be a seemingly endless list of potential problems that can cause it to pop out, and this is because so many different components on a car can affect the engine.

Whether it may be something minor like an open gas cap or something more serious like a cylinder misfiring, it can be tricky to figure out what’s the exact cause of a check engine light without other signs.

Sometimes, a check engine light may be accompanied by the presence of another warning light, such as a “Trac Off” light, which would narrow it down to an issue with the traction control system.

Because of this, a check engine light should be immediately diagnosed through a scanner such as an OBD-II reader in order to check if there are any error codes stored in the vehicle’s ECU.

What is the VSC System on a Toyota Corolla?

The VSC (Vehicle Stability Control) System is a safety feature on Toyotas that prevents the wheels from skidding while cornering and maintains your vehicle’s direction of travel.

Once engaged, the VSC system will turn on a “VSC” light that will appear on the dashboard or gauge cluster.

What is the VSC System on a Toyota Corolla

The Toyota Corolla and other Toyota and Lexus models have what is called a Vehicle Stability Control (VSC) system that works in line with the Traction Control system in the vehicles as well.

As the main form of stability control or assist for the Corolla, the VSC system aims to keep your wheels from slipping when turning by adjusting the power and applying the necessary braking force to the wheel that needs it.

This makes the VSC quite similar to how the Traction Control (TRAC) system works. However, the main difference is that the TRAC system only prevents wheel slip, while the VSC also maintains your car’s direction of travel when cornering.

The VSC system has its own separate light that simply says “VSC” or “VSC OFF” on the dashboard. Cars like the Toyota Corolla also have a dedicated VSC button underneath the AC vent located to the right of the steering wheel.

What is the VSC System on a Toyota Corolla

What causes the “Trac Off” and “Check Engine Light” to appear on a Toyota Corolla?

The Trac Off light and check engine light can turn on due to a bad traction control switch, faulty brake light switch, faulty ABS, and bad shift interlock solenoid.

The Trac Off light may turn on if the traction control button has been accidentally turned off, or you have low oil or tire pressure. 

Bad Traction Control Switch/Button

Bad Traction Control Switch/Button

When you have both a Trac Off light and check engine light illuminated on your Corolla’s dash or gauge, then one of the most likely culprits is a bad traction control switch or button.

The traction control switch or button gives you the choice of turning off your traction control manually, though when it malfunctions, it can suddenly turn it off without you knowing right away.

On Toyota Corolla models, the traction control button is most commonly located under the right vent next to the steering wheel. But it may also be located on the left side or at the bottom of the gear shifter.

If you’ve confirmed that the traction control button is faulty or not responding, then you need to get it replaced, which costs $20 to over $60 in parts depending on your exact Corolla model.

Faulty Brake Light Switch

One other reason that you may not have expected can trigger the Trac Off light to turn on is a faulty brake light switch.

This little switch that’s located behind your brake pedal activates the brake lights every time you step on the brakes.

Since the Traction Control system also utilizes the brakes to function properly, a malfunction in the brake light switch can also turn on the Trac Off light. 

Accidentally Turning Off Traction Control (TRAC/VSC Button)

Now sometimes, the Trac Off light turning on isn’t necessarily due to an issue with the traction control system itself, as you may have accidentally just pressed the traction control button on your car.

If you have never turned off the traction control in your car before, then it can be pretty easy to push it unintendedly while you’re fiddling around with your car’s interior features.

The Toyota Corolla, in particular, can have its traction control button in different places depending on the exact model and year, like either under the left or right AC vent or next to the gear shifter.

The button itself is labeled with a small car with tire marks and the word “OFF” below it. It doubles as the Trac Off button (short press) and the VSC Off button (long press).

Simply pushing the button again will turn the traction control back on and turn off the “Trac Off” light on the dash. Alternatively, traction control activates automatically every time you start the car again.  

Faulty Antilock Braking System (ABS)

Faulty Antilock Braking System (ABS)

Traction Control systems, such as that of Toyota’s “TRAC” system, also make use of the vehicle’s brakes to prevent the wheels from slipping on any slippery road surface.

With that in mind, the TRAC system also works closely together with the ABS or “Antilock Braking System”, which is tasked to prevent the wheels from locking up under heavy braking.

Thus, if something goes wrong with the ABS system, then the TRAC system’s performance will be affected and you’ll most likely get a “Trac Off” light on your dashboard as well.

If you have a problem with your ABS system, then it’ll also have its own warning light illuminated on the dashboard, which is usually labeled as “ABS” or an exclamation point with “BRAKE” underneath it.

Moreover, it’s also important to check the ABS module itself or your wheel speed sensors. We recommend getting any ABS problems diagnosed by a mechanic for proper repairs or replacements.

Faulty Shift Interlock Solenoid

Another component that can cause your Trac Off light to turn on is the shift interlock solenoid, which is essentially a switch that keeps your vehicle locked in “Park” whenever you turn off the engine or you’re not pushing the brake pedal.

A shift interlock solenoid can fail in two ways, either in the disengaged position or the engaged position. If it was disengaged the last time you used your vehicle, then you’re more likely to experience the Trac Off issue, and here’s why.

A faulty shift interlock solenoid in the disengaged position may not keep your vehicle in “Park”, and since traction control can only initially engage when the vehicle is not moving, it may not turn on automatically when you start the engine.

Not only can this cause the Trac Off light to turn on, but you’re also unprotected from accidentally shifting into other gears even if you don’t have your foot on the brake pedal.

Low Oil Pressure

Low Oil Pressure

Despite being electronically controlled, the traction control system involves many different mechanical components that are lubricated and cooled by oil.

If your vehicle loses oil pressure, then it can significantly affect the performance of such mechanical components, like your engine internals, which can potentially deactivate traction control and turn on the “Trac Off” light.

The traction control system relies on the engine to make power adjustments to the wheels in the event that they’re slipping. So if the engine was to overheat because of low oil pressure, it can cause the traction control to turn off as well.

Low Tire Pressure

Low Tire Pressure

Your vehicle’s tires are your main contact points with the road surface, so if you’re running with lower tire pressure, this can affect how your traction control engages under slippery conditions.

If your vehicle detects even one tire that has a lower psi reading than the rest, then there will be a difference in traction performance between it and the other tires, which may be interpreted by the vehicle as a problem with the traction control system.

In this case, the Trac Off light would be turned on not because traction control has actually been disabled, but because of a potential issue with the traction control system. Again, this is the other job of a Trac Off light that some may not be aware of.

However, there’s a chance that your tire pressure is actually correct, yet the TPMS (Tire Pressure Monitoring System) sensor is faulty and sending incorrect pressure readings to the ECU, so this is something worth inspecting as well. 

What happens when the “Trac Off” and check engine lights appear?

A Trac Off light accompanied by a check engine light can mean that traction control has been switched off due to a problem with the engine that can affect its performance.

A direct issue with the traction control system can also cause the Trac Off light and check engine light to turn on.

How to Fix Toyota Corolla Trac Off and Check Engine Light (Zero Point Calibration)

An alternative method of fixing the Trac Off light and the check engine light on a Toyota Corolla is performing a zero-point calibration.

The zero-point calibration procedure for the Toyota Corolla can be used to recalibrate sensors for the VSC (vehicle stability control) and clear warning lights.

How to Perform Zero Point Calibration on a Toyota Corolla:
1. Park the vehicle on a level surface.
2. Unplug both positive and negative battery cables (negative first) for 5 minutes.
3. Reconnect both battery cables (positive first) again.
4. Locate the OBD port, which is typically underneath the steering wheel on the left side of the dashboard.
5. Using a repair manual for your particular vehicle model as a reference, locate the “CG” and “TS” terminals on your OBD port.
6. Get two small metal paper clips and straighten them out completely.
7. Insert one paper clip in the “CG” terminal and the other one in the “TS” terminal while making sure the other ends of the paper clips are not touching anything.
8. Bend one of the paper clip ends to the left and the other one to the right while still maintaining no contact between them.
9. Afterward, touch the two free ends of the paper clips together at least 4 times within 8 seconds.
10. Ensure your front wheels are pointed straight and your steering wheel is perfectly centered.
11. Insert your key in the ignition and turn it to the “on” position without actually starting the engine.
12. The gear shifter should be in “Park” (auto transmissions) or the handbrake should be engaged (manual transmissions).
13. The next steps should be performed carefully without moving any part of the vehicle in any way, as this may disrupt the calibration process.
14. Touch the paper clip ends together 6 times, then wait for both the VSC and ABS lights to flash together slowly but not in unison. This means that calibration has been reset for the systems.
15. Turn the ignition key off, touch the two paper clips together, then turn the key to the “on” position again without starting the engine.
16. Check if the VSC and ABS lights start flashing faster and in unison this time. This means that they’ve been successfully recalibrated. 
17. Turn the ignition key to the “off” position, remove the two paper clips from the OBD port, and then turn the key to the “on” position again.
18. You should notice that the VSC light, ABS light, and other related warning lights such as the “Trac Off” light will be cleared from your dashboard or gauge.
19. To finish the calibration procedure, do a test drive and maintain a speed of at least 25 mph (40 km/h) while making sure to drive as straight as you can for 10 seconds.

How to Prevent Problems With Your Traction Control System (TCS/TRAC System)

Traction Control System problems can be prevented by doing regular maintenance on your car, avoiding driving in harsh or extreme conditions, and keeping your vehicle’s software updated at all times.

How to Prevent Problems With Your Traction Control System (TCS/TRAC System)

Doing Regular Maintenance

Following the recommended maintenance intervals for your car’s components can reduce the chances of something going wrong with your traction control system.

Whether it’s getting your oil changed regularly or having your tires inflated properly and replaced at the recommended mileage, regular maintenance can ensure that your traction control system engages and performs properly under all conditions. 

Avoiding Driving in Harsh or Extreme Conditions

While it’s the traction control system’s job to prevent your wheels from slipping on any slippery surface, this doesn’t mean that you can just drive on any terrain without any consequences.

If you keep driving in harsh or extreme road conditions, then you can risk putting too much load on the traction control system and potentially cause it to underperform or malfunction.

So unless you absolutely need to go down this certain route, it’s recommended to avoid driving on roads that neither your traction control nor your entire vehicle was exactly built for.

Keeping Your Vehicle’s Software Updated

Traction control systems, especially more modern ones, run on the vehicle’s software to perform its operations, so it’s important to keep the software up to date so that your traction control is always performing optimally with no errors or glitches.

Frequently Asked Questions (FAQs)