How the Circuit Works: Notes

The multiplex integrated control system sends digital signals between control units through shared wires to reduce the number of wires in order to make harnesses lighter.

The input signals from each switch are converted to digital signals within the receiving control unit. The digital signals are sent from one control unit to another as serial data over dedicated communication lines. When the appropriate control unit receives the digital signal, it converts the signal back to an operational command, such as operating a relay. The multiplex integrated control system schematic shows power, grounds, and communication lines. The ignition key light and roof console are shown because they are used to blink DTCs when the system is in the self-diagnostic mode.

There are two different networks within the multiplex integrated control system. They are:

• Body Controller Area Network (B-CAN)
• Fast Controller Area Network (F-CAN)

The body controller area network (B-CAN) transmits information at 33.33 kbps and the fast controller area network (F-CAN) transmits information at 500 kbps. Both networks share information among multiple electronic control units and work together to form the multiplex integrated control system. The gauge control module translates information from B-CAN to F-CAN and from F-CAN to B-CAN to allow the networks to share information.

The driver's door lock switch links directly to the driver's MPCS unit, and the front passenger's door lock switch links directly to the front passenger's MPCS unit. All lock and unlock commands from this switch are communicated across the multiplex integrated control system to the MICU.