The low tire pressure warning light will typically go off *automatically* once you inflate the tires to the correct pressure (printed on a sticker inside the driver's side doorjamb) and drive for a short distance. The system needs to detect the change in wheel speed to know the pressure is back to normal.
If the light stays on *even after* you've properly inflated your tires and driven a bit:
* Check your tire pressure again: Ensure all tires are at the correct pressure, including the spare if applicable. Use a reliable gauge.
* Check for a faulty sensor: If your Impala uses an indirect TPMS system (which is very likely), there might be a problem with one of the ABS wheel speed sensors. A malfunctioning sensor can trigger the low tire pressure light, even with properly inflated tires. This will require professional diagnosis and repair.
* Look for other issues: A flat tire, slow leak, or significantly different tire sizes can trigger the warning light.
If you've addressed tire pressure and there's still an issue, take your Impala to a mechanic or tire shop for a proper diagnosis. They'll be able to check the tire pressure, assess the sensor functionality, and identify any problems with the TPMS or related systems.
