Theory Of Operation
WARNING: This page is about a different car, the 2013 RAM 3500 HD and 2013 RAM 2500 HD. However, it is still accessible from the selected car via links, so may be relevant.
The Body Control Module (BCM) provides a battery voltage output to certain lamps through the courtesy lamp circuit. These lamps use a dedicated path to ground for illumination. The same lamp may also use a reading lamp circuit, which uses a switched path to ground for illumination. For additional information on the operation of the Courtesy Lamps. Refer to OPERATION .