FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
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Circuit Description

MULTIPLEX CONTROL SYSTEM

How the Circuit Works

The conventional portion of the electrical system carries DC 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 the multiplex control unit to components 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, ceiling and spotlights are also shown because they are 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:
- Low Oil Pressure Indicator Light
- Seat Belt Reminder
- Lights-on Reminder
- Key-in Reminder
- Entry Light Control System
- Power Door Locks
- Wiper/Washers
- Keyless Security Alarm System
- Interlock System
- Map Light/Spotlight
- Headlights