General Module: Description and Operation

How the Circuit Works
The conventional portion of the electrical system carries DC (or A/C) power through separate wires to each component. The multiplex portion of the system, however, sends digital signals between control units through shared wires to reduce the number and weight of wire harnesses. The signals from each switch are converted to digital signals within the receiving multiplex control unit. The digital signals are sent from one multiplex control unit to another as serial data over dedicated communication lines. When the appropriate control unit receives the digital signal, it converts it back to a switch signal and operates the related components.

The multiplex control system schematic shows it's power, grounds, and communication lines. The ignition key light is also shown because it is used to blink DTCs in the system's self-diagnosis function. The rest of the multiplex control system wiring is shown in the following circuit schematics:
- Engine Oil Pressure Indicator Light
- Seat Belt Reminder
- Lights-on Reminder
- key-in Reminder
- Entry Light Control System
- Dash and Console Lights (brightness control)
- Headlights with Auto-off Function
- Power Door Locks
- Power Windows
- Wiper / Washers
- Keyless Entry / Security Alarm System
- Interlock System