Possible Causes:
* Low tire pressure: This is the most common and easiest to fix. Check the tire pressure in all four tires and inflate them to the recommended pressure (found on a sticker usually located on the driver's side doorjamb or in your owner's manual).
* Faulty wheel speed sensor: These sensors monitor wheel rotation speed. A faulty sensor can cause inaccurate readings, triggering the STC light. This requires a mechanic to diagnose and replace the faulty sensor.
* Faulty ABS sensor: The Anti-lock Braking System (ABS) and Traction Control are closely related. A problem with an ABS sensor can also trigger the STC light. Again, a mechanic's diagnosis is needed.
* Problem with the traction control module: This is the computer that controls the traction control system. A malfunctioning module will require professional diagnosis and likely replacement.
* Brake system issues: Low brake fluid, a faulty brake switch, or other brake system problems can sometimes trigger the light. Have your brakes inspected.
* Wiring issues: Damaged or corroded wiring related to the traction control system can cause malfunctions.
* Failing TCM (Transmission Control Module): In some cases, a problem with the TCM can also affect the traction control system.
Troubleshooting Steps:
1. Check tire pressure: This is the first and most important step.
2. Check for any other warning lights: Are the ABS or brake lights also on? This could provide additional clues.
3. Clear the code (if possible): Some OBD-II scanners can clear trouble codes. This might temporarily turn off the light, but the problem will likely reappear if it's not fixed. However, clearing the code *before* getting a proper diagnosis can erase valuable information.
4. Have it professionally diagnosed: Take your Impala to a qualified mechanic or auto parts store that can perform a diagnostic scan. This will identify the specific trouble code(s) and pinpoint the problem.
Important Note: Driving with the STC light on means your traction control system isn't working as designed. This can reduce your ability to maintain control, especially in slippery conditions. While it might not be an immediate emergency, it's best to have it diagnosed and repaired as soon as possible.
