What Are ASC System Service Required?

The active stability control takes overall control of the anti-lock brake system, traction control function, and stability control function to help maintain the vehicle’s control and traction.

An anti-lock brake system, ABS, is a system that is designed to prevent you from locking up your brakes. Also applying so much pressure to your brakes that the axle and your wheels themselves stop turning completely.

On slippery surfaces, the traction control function prevents the drive wheels from spinning excessively. Thus helping the vehicle to start moving from a stop condition. It also provides sufficient driving force and steering performance as the vehicle turns while pressing the acceleration pedal.

The stability control function is design to help the driver maintain control of the vehicle on slippery roads or during rapid steering. It works by controlling the engine output and the brake on each wheel. To know the possible symptoms of ASC system service required to follow below.

How Does ASC Work On Your Vehicle?

In some extreme driving conditions, the vehicle is not traveling in the direction that the steering wheel is pointing, the ASC will reduce engine power and apply brakes to individual wheels to return the vehicle to the intended path.

There are many names for activity stability control, but they all perform similar functions. Refer to the owner’s manual for specific information on how ASC works on your vehicle.

What Are The Symptoms Of ASC System Service Required?

There are several symptoms below. To know better about the ASC system follow below

  • When driving in unsafe conditions, the ASC light does not blink.
  • The ABS doesn’t engage under a panic stop.
  • You have a loss of traction due to the 4WD being disengaged.
  • ASC System Service Required message showing in the vehicle display and the ASC warning light illuminated on the dashboard.
  • Noticeable wheelspin during aggressive accelerations from standstills. This will also happen when going up steep inclines when the traction is poor.
  • Loss of traction when going through tight corners at higher speeds. Depending on driving conditions, the vehicle might either oversteer or understeer.
  • The engine may not start even with no cranking action after turning the key. In most cases, this will start as an occasional issue that also triggers the ASC warning message.
  • Cruise control no longer is enabled.
  • ASC Off means transmission will no longer change gears. Typically will get stuck in second gear.
  • Beeping for several minutes when you start to drive.
  • 4WD light flashing on and off.

What Causes ASC Warning?

The most common problems that trigger the ASC warning light are:

1. ABS Wheel Speed Sensor

The ABS wheel speed sensor issue provides information about the wheel speed to the ASC computer. There are four sensors, each at one wheel. The sensor itself can go bad with time; it is wise to check for damaged wiring or loose connectors. Sometimes, going through deep water or snow can disrupt the sensor readings, but this usually goes away quickly.

2. Brake Pedal Switch

Various on-board computers use brake pedal switch signals to determine if the brake pedal is pressed or not. Most cars don’t allow drivers to start the engine without pressing the brake pedal. Because a faulty switch will cause non-starting issues. And even if it starts, this will still trigger the ASC system service required.

3. Brake Light Bulb

Brake light bulb issues as seemingly unrelated can cause ASC warning messages. The cause for this can be something like corroded connectors or aftermarket LED bulbs with incorrect resistance. A blown brake light fuse will have an identical effect.

4. Misalignment Wheel Size

Misaligned or unevenly worn tires, different size tires may offset the steering wheel angle sensor or difference in wheel spin speeds. The ASC computer won’t perform correct calculations because the steering wheel or ABS sensor will provide impossible readings.

The ASC system is not crucial to operating the vehicle, but it is a good safety net when conditions become unsafe. 

In case the ASC Service Required light activates and will not go off, take your car to a trusted mechanic or the dealer and have them diagnose the problem.

5. Other

If the ASC service required message comes up on the dashboard, turn off the engine, remove the key from the vehicle, wait a few minutes, then restart the car.

In many cases, this simple procedure will reset the ASC warning message. If the ASC service light stays on, take a look at the common problems and the steps below on troubleshooting the ASC system.

ASC warning display

If an abnormal condition occurs in the system while driving, the  ASC OFF display will blink or the warning display shows “SERVICE REQUIRED” and the display will be displayed at the same time.

1. Malfunctioning

If the warning display, “SERVICE REQUIRED” and the “ASC OFF “display are shown at the same time. The system may be malfunctioning. Park your vehicle in a safe place and stop the engine.

Restart the engine and check whether the warning display, “SERVICE REQUIRED” and the display go out or not. In case the warning display goes out, there is no abnormal condition. If the warning display does not go out or appears frequently, it is not necessary to stop the vehicle immediately. But we recommend you to have your vehicle inspected.

2. ASC OFF Display Blinks

If the ASC OFFdisplay blinks and if the temperature in the braking system continues to increase due to continuous brake control on a slippery road surface, the display will blink and operation of the traction control function will be suspended to protect the brake system. Park your vehicle in a safe place. When the temperature in the braking system has come down, the ASC OFF display will be turned off and the traction control function will start operating again.

How To Turn Off ASC Light?

On your dashboard, there is an ASC button that may have been pressed accidentally. If that’s the case you can manually turn the ESC light off.

  • Start the car.
  • Find the switch that says ESC on the dash and press it for three seconds.
  • Look at your instrument cluster to see if the light turned off.
  • ASC button

What Is The Cost Require To Repair ASC?

It estimates that the average cost for installation of the ASC will be around 111$ per vehicle on vehicles that already include ABS brakes with mass production. Currently, the cost for optional equipment is around 300$ to 800$.


When moving out of mud, sand, or fresh snow, pressing the accelerator pedal may not allow the engine speed to increase. In such situations, temporarily turning off the ASC with the ASC OFF switch will make it easier to move out your vehicle.
Using the “ASC OFF” switch turns off both the stability and traction control functions. If you continue to press the “ASC OFF” switch after the ASC is turned off, the “mistaken operation protection function” will activate and the ASC will turn back on.

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