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Description & Operation

WARNING: Deactivate air bag system before performing any service operation. See AIR BAG RESTRAINT SYSTEMS article. DO NOT apply electrical power to any component on steering column without first deactivating air bag system. Air bag may deploy.

The multiplex control system is controlled and monitored by the body Electronic Control Unit (ECU). Other components in the system include power window master switch, ECM, theft deterrent ECU, instrument cluster ECU and A/C ECU. See Fig 1. Theft deterrent ECU is located to right side of driver-side junction block ECU.

Fig 1: Identifying Multiplex Control System Components
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