Circuit/System Description
WARNING: This page is about a different car, the 2017 GMC Acadia. However, it is still accessible from the selected car via links, so may be relevant.
The steering wheel heating control module controls the heated steering wheel and the heated steering wheel ON indicator based on an input from the steering wheel controls switch - left. When the steering wheel heat switch is pressed, the switch signal circuit is pulled to ground. This indicates to the steering wheel heating control module that steering wheel heat is requested. When the request is seen, the steering wheel heating control module provides a ground to the indicator lamp and supplies voltage to the heating elements, which are internal to the steering wheel.