Principles of Operation

PRINCIPLES OF OPERATION

The smart junction box (SJB) controls the exterior lighting of the vehicle. This system relies on the standard corporate protocol (SCP) communication network in order to transmit and receive signals. It is very important to understand:
- where the input (command) originates from.
- all information (messages) necessary in order for a feature to operate.
- which module(s) receive(s) the input or command message.
- if the module which received the input (message) controls the output of the feature, or does it output a message over the SCP communication network to another module.
- which module controls the output of the feature.

The reversing lamps are controlled by the SJB and the powertrain control module (PCM). The PCM sends a message through the SCP communication network to the SJB indicating the transmission is in REVERSE. The SJB processes this information and outputs the command to the reversing lamps which are hard-wired to the SJB.