Trailer Hazard Lamp Operation
WARNING: This page is about a different car, the 2011 Suzuki Equator. However, it is still accessible from the selected car via links, so may be relevant.
The trailer hazard lamps are controlled by the BCM. When the hazard switch is pressed, the BCM detects the hazard ON request. The BCM then sends a control signal to both trailer turn relays which sends power to the trailer connector.