Theory Of Operation
WARNING: This page is about a different car, the 2024 RAM ProMaster EV. However, it is still accessible from the selected car via links, so may be relevant.
When the ignition is on, the Body Control Module (BCM) provides a constant voltage input signal to the Left and Right Front Lamp Assemblies, through the Lighting Fault Sense circuits.
When the Turn Lamps are activated, the Body Control Module (BCM) provides an additional voltage signal to the Lamp Assemblies, through the Left or Right Front Turn Lamp Driver circuits, indicating the Turn Lamps have been requested.
When the Left or Right Turn Lamps are activated, an internal driver within the Lamp Assembly pulls the Lighting Fault Sense circuit voltage input signal low, in sequence with the Turn Lamp flash.