Circuit/System Description
WARNING: This page is about a different car, the 2007 Suzuki XL7. However, it is still accessible from the selected car via links, so may be relevant.
The body control module (BCM) applies a ground through the brake pedal position sensor low reference circuit to the brake pedal position sensor (BPP). The BCM supplies a 5-volt reference through the brake sensor reference voltage circuit to the BPP. When the brake pedal is being applied, the BPP then sends a variable voltage through the brake sensor signal circuit to the BCM. The BCM then applies a signal to the brake signal circuit to the engine control module (ECM) and transmission control module (TCM).