Circuit/System Description
WARNING: This page is about a different car, the 2008 Suzuki XL7. However, it is still accessible from the selected car via links, so may be relevant.
The body control module (BCM) controls the fog lamps based on inputs from the fog lamp switch. When the fog lamp switch is pressed, a ground path is provided on the front fog lamp switch signal circuit to the BCM, indicating the front fog lamps ON command. In response to this signal, the BCM grounds the fog lamp relay control circuit energizing the FOG LAMP PCB Relay. With the fog lamp relay energized, battery voltage is applied through the FOG Fuse and the fog lamp supply voltage circuits illuminating the front fog lamps.
When a fog lamp request is seen by the BCM, a serial data message is sent to the instrument panel cluster (IPC) requesting the fog lamp indicator be illuminated.