Circuit/System Description
WARNING: This page is about a different car, the 2010 GMC Canyon and 2010 Chevrolet Colorado. However, it is still accessible from the selected car via links, so may be relevant.
After the traction control switch (TCS) is pressed and released, the LED on the switch illuminates. The body control module (BCM) illuminates the LED by supplying adequate current to the high side of the LED.