"Check VSC" in Lexus IS250. We Explain What to Do

Did your Lexus IS250 illuminate the check VSC light? Are you wondering what this means and what you should do about it? Don't worry. This article explains vehicle stability control, VSC warning light, and what to do when the light comes on. 

Check VSC message highlights

• Common reasons:issues in stability control function
• How to fix:disconnect the battery for some time, read the codes
• Possible consequences:vehicle's behavior may change
• Priority level:High
• Can you drive?Carefully
• DIY repair:Impossible
• Repair price range:$200-$850

What is Vehicle Stability Control?

Vehicle stability control is a safety system installed in several Toyota and Lexus vehicles. The cars installed with this system include Toyota Camry, Avensis, Lexus RX400H, and Lexus IS250, among other models.

The VSC system prevents your Lexus IS250 from slipping or sliding when you drive in adverse conditions. During extended precipitation, the roads become slippery, causing serious trouble for the tires trying to gain grip. Vehicle stability control aims to keep your vehicle stable on the road.

How does it Work?

The VSC system is designed to provide traction for your Lexus IS250. It regulates your vehicle's internal traction control system and commands it to come to life when needed. The vehicle stability control system automatically comes to your aid when you drive on slippery and unstable roads. It enhances the wheels' traction and gives you better steering control to navigate difficult roads.

The VSC system relies on the powertrain control module for better performance. Every wheel on your IS250 has a speed sensor that constantly sends signals to the PCM as you drive. When one or more of these sensors detect a problem with traction, it immediately sends this data to the PCM, which transmits it to the vehicle stability control system. The VSC uses this data to command the internal traction and steering control systems to stabilize your vehicle.

The vehicle stability control in your Lexus VSC works by reducing or increasing engine power when your vehicle needs stability enhancement. Additionally, it uses an anti-lock braking system to minimize the motion when one or more wheels lose traction.  

Check VSC Light

The check VSC warning light illuminates when there's a problem with your vehicle stability control system. The light may also come on if you press the VSC button accidentally. Traction control helps improve your vehicle's grip on the road. It works closely with the ABS, applying brakes automatically to minimize motion.

When you see the VSC warning light, these two systems, TCS and ABS, are disabled and will not deploy when you lose traction.

What Causes the Check VSC to Illuminate?

Since the VSC and ABS work together to enhance the stability of your vehicle, the VSC light is sometimes followed by the ABS light. The two lights, VSC and ABS, may also be accompanied by the check engine light, especially if there is a problem with the ECM.

The following are some possible causes of the VSC light.

1) Malfunctioning Brake Light Switch

The brake light switch, located at the brake pedal, is responsible for turning the brake lights on when you press the pedal. The switch also sends signals to several control systems when you apply brakes. One of these control systems that rely on the data transmitted by the brake light switch is the VSC. When there is a problem with the brake light switch, the powertrain control module stores a fault code, which triggers the VSC light.

2) Your Lexus Engine has Problems

This is the primary reason the VSC warning light is on, especially if the check engine light accompanies the VSC warning light.

Your Lexus IS250 comes with multiple sensors and actuators that send data to several control modules for the proper functioning of your vehicle. One of these control systems is the VSC. When there is a problem with your engine, other control systems, like the VSC, will not function properly, which causes the VSC light to come on.

When this happens, it becomes difficult to guess the reason for the light. You will need to use an OBD2 scanner to isolate the problem causing the lights to come on and fix it.

Some possible engine problems that may trigger the VSC light include a faulty MAF sensor, a malfunctioning oxygen sensor, a loose gas cap, and a bad accelerator pedal, among other issues.

3) Bad ABS Sensor/s

Every wheel on your Lexus IS250 has a wheel speed sensor. Besides the anti-lock braking system, other essential control systems use the data provided by these sensors to execute their mandates. Such control units include the engine and transmission control modules.

These sensors are found at the wheel spindle hubs and are prone to failure due to exposure to water, dirt, and other unfavorable external conditions.

Since the vehicle stability control system of your IS250 relies on these sensors, the VSC light will come on when there's a problem with one or more of them. A faulty ABS can also be caused by malfunctioning ABS Reluctor rings, which the ABS sensor uses to measure wheel speed. There could also be an issue with wiring or connections.

Other possible causes of the VSC warning light include wiring issues or pushing the VSC button unknowingly.

What to Do When the Check VSC Light Comes On

When the VSC warning light comes on, you will need to perform a few activities to identify the problem so that you can fix it.

• Start by Reading Trouble Codes

There are several reasons the VSC light comes on. As a result, you must use an OBD2 scanner to scan every control module related to the vehicle stability control before doing anything else.

The advanced diagnostic software in your Lexus IS250 will tell you precisely what is ailing your VSC system. This will help save you time so that you don't measure every control sensor in your vehicle to determine the problem.

• Check Your Brake Light Switch

Checking the brake lights is a simple, quick fix that could erase the VSC problem in seconds. Since the brake light switch directly communicates with the VSC system, the VSC light will come on if it fails.

To check your brake light switch, have a friend stand behind your car and let you know whether the brake lights illuminate when you press the pedal. If they don't, you just cracked your VSC light case.

• Check Your Brake Fluid

Low brake fluid levels could significantly affect the anti-lock braking system, which could also affect the proper functioning of the vehicle stability control.

You should start by checking the brake fluid reservoir. If you notice low levels, it is the reason for the VSC light. A leak around the brakes could cause low brake fluid. Confirm if there are any leakages that need to be fixed, and then refill the brake fluid reservoir.

• Check if the Gas Cap is Loose

This is primarily possible if the check engine light accompanies the VSC light. If the gas cap is loose or leaking, the engine light will illuminate, followed by the VSC light. If the lights come on after a refuel, the problem is a loose gas cap.

The light might also illuminate when you leave the engine running with the gas cap off when refueling. In this case, a simple reset will clear the trouble code, and the VSC light will go off. If the gas cap is leaking, you'll need to inspect the O-rings around it to ensure they seal tightly to avoid leaking.

If you have done all the above and there's no change, it is time to consult a professional for assistance.

How to Reset the VSC Light on A IS250

If the VSC light on your vehicle is on, you can do a few things to reset it. Start by ensuring that you didn't accidentally press the VSC button. If you did not, follow these simple steps to reset the vehicle stability control light on your IS250.

• Ensure your Lexus IS250 is parked on level ground and the gear lever is in Park.
• Locate the VSC button. The VSC button can be found behind the gear shift stick on some IS250 models and next to the steering wheel on others.
• Press the VSC button until the VSC OFF, and TRAC OFF lights appear.
• Release the VSC button, and press it again, normally this time. You should see the VSC OFF and TRAC OFF lights go off, which means your VSC system has been restored and the traction control is active.

Should I Drive My IS250 With the VSC Light On?

Traction control is not a determinant of whether your vehicle will move. Without it, your vehicle will still move, and the fuel economy will not suffer. However, vehicle stability control is an excellent safety feature that has helped many Lexus IS250 owners avoid accidents caused by slippery roads. That said, you should always ensure that the system is working correctly.

In some instances, you should avoid driving with the VSC light on. These instances include;

• When the check engine warning light is on.
• When the ABS warning light is on.
• If your vehicle is behaving strangely and producing strange noises and odors

Conclusion

Your Lexus IS250 features a superb stability control system called the VSC. It helps you remain stable on slippery roads. The VSC works closely with your vehicle's ABS to minimize accidents in adverse conditions. When this system fails, it notifies the driver via a dashboard warning light called the VSC light. If you own a Lexus IS250, follow the above steps if you ever experience the VSC light coming on.