Nissan Maxima Service and Repair Manual: System description

  • Body control system
  • System Description OUTLINE ECU DIAGNOSIS INFORMATION controls the various electrical components. It inputs the information required to the control from CAN communication and the signal received from each switch and sensor. BCM has combination switch reading function for reading the operation status of combination switches (light, turn signal, wiper and washer) in addition to a function for controlling the operation of various electrical components. It also has the signal transmission function as the passed point of signal and the power saving control function that reduces the power consumption with the ignition switch OFF.

  • Combination switch reading system
  • System Diagram System Description OUTLINE BCM reads the status of the combination switch (light, turn signal, wiper and washer) and recognizes the status of each switch. BCM has a combination of 5 output terminals (OUTPUT 1 - 5) and 5 input terminals (INPUT 1 - 5) and reads a maximum of 20 switch states. COMBINATION SWITCH MATRIX Combination switch INPUT-OUTPUT system list COMBINATION SWITCH READING FUNCTION Description BCM reads the status of the combination switch at 10ms intervals normally. NOTE: BCM reads the status of the combination switch at 60ms intervals when BCM is controlled at low power consumption mode. BCM operates as follows and judges the status of the combination switch.

  • Signal buffer system
  • System Diagram System Description OUTLINE BCM has the signal transmission function that outputs/transmits each input/received signal to each unit.

  • Power consumption control system
  • System Diagram System Description OUTLINE BCM incorporates a power saving control function that reduces the power consumption according to the vehicle status. BCM switches the status (control mode) by itself with the power saving control function. It performs the sleep request to each unit (IPDM E/R and combination meter) that operates with the ignition switch OFF.

  • Diagnosis system (BCM)
  • COMMON ITEM COMMON ITEM : CONSULT Function (BCM - COMMON ITEM) APPLICATION ITEM CONSULT performs the following functions via CAN communication with BCM. Direct Diagnostic Mode Description Ecu Identification The BCM part number is displayed Self Diagnostic Result Displays the diagnosis results judged by BCM Data Monitor The BCM input/output signals are displayed Active Test The signals used to activate each device are forcibly supplied from BCM Work support Changes the setting for each system function Configuration Enables to read and save the vehicle specification. Enables to write the vehicle specification when replacing BCM.

Configuration (BCM)

Body control system