One problem related to brake antilock wheel speed sensor has been reported for the 2003 Chevrolet Impala. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2003 Chevrolet Impala based on all problems reported for the 2003 Impala.
Anti-locking braking system, traction control, and vsa light comes on under normal driving conditions. Anti-lock system engages and pulsates when the brakes are applied at various speeds and also the vehicle doesn't' accelerate if depressing the accelerator. This could or will cause a serious accident if the system is not fixed immediately. Suspect the wheel speed sensor which is built into the wheel hub. I am requesting this issue be repaired and the factory expense since this is a safety issue and a very well know documented case.