Information Bus: Description and Operation

COMMUNICATIONS NETWORK

Anti-Lock Brake System (ABS) Module
The ABS module (if equipped) is on the high speed controller area network (CAN). The high speed CAN is used by the ABS module for communicating with the diagnostic tool. The ABS module controls the brake pressure to the 4 wheels to keep the vehicle under control while braking.

Electronic Automatic Temperature Control (EATC) Module
The EATC module is located in the instrument panel below the audio unit. The EATC module is on the medium speed CAN. The EATC module controls automatic climate functions that maintain the vehicle interior temperature at a constant setting.

Smart Junction Box (SJB)
The SJB is on the medium speed CAN. The SJB is equipped on all vehicles. The SJB is a combination of a multifunction control module and an interior power junction box. SJB functions control multiple systems which include:
- speed dependent interval windshield wipers
- illuminated entry and interior lamps
- power door locks
- windshield wipers
- warning chimes
- battery saver
- accessory delay
- power windows

Restraint Control Module (RCM)
The RCM is the only module on the international standards organization (ISO) 9141 communication network. The RCM controls the deployment of the air bags based on sensor input.

Powertrain Control Module (PCM)
The PCM is on the high speed CAN. The PCM controls the engine for better fuel economy, emissions control, failure mode detection and storage. Refer to Computers and Control Systems for diagnosis and testing of the PCM.

Passive Anti-Theft System (PATS)
The PATS is integrated into the PCM. The PCM controls the PATS functions as well as illumination of the anti-theft indicator. The PCM stores the ignition key codes and controls engine disable.

Instrument Cluster
The instrument cluster is on the high speed CAN. It is an analog face cluster with a digital odometer. The instrument cluster displays a variety of information.