Circuit/System Description

When the headlamp switch is placed in either the park or low beam position, ground is applied to the tail lamp signal circuit to the body control module (BCM). The brake pedal position sensor provides an analog voltage signal to the BCM. The BCM sends this messages to the trailer lighting converter. The trailer lighting converter responds by applying battery voltage to the left tail lamp and to the right tail lamp control circuits. This energizes the tail lamps.