Controller Area Network (CAN)

WARNING: This page is about a different car, the 2021 Ford F-150. However, it is still accessible from the selected car via links, so may be relevant.

The CAN is based on society of automotive engineers (SAE) J2284, international standard organization (ISO)-11898, and is a serial communication language protocol used to transfer messages (signals) between electronic control modules or nodes. Two or more signals can be sent over one CAN circuit allowing 2 or more electronic modules or nodes to communicate with each other. This communication, or multiplexing, network operates at 500k/sec (kilobytes per second) and allows the electronic modules to share their information messages.

Included in these messages is diagnostic data sent over the CAN+ and CAN- lines to the DLC. The PCM connection to the DLC is done with a twisted pair cable used for network interconnection. The diagnostic data such as self-test or PID can be accessed with a scan tool. Refer to the appropriate article for more information.

The increased number of modules on the vehicle dictate a more efficient method of communication. Multiplexing is the process of communicating several messages over the same signal path. This process allows multiple modules to communicate with each other through the signal path (CAN2+ and CAN2-). The glow plug control module (GPCM) and nitrogen oxides (NOx) modules communicate with the PCM using CAN2 communications, to determine the priority in which the signals are sent. Refer to the CAN for additional information.