Nissan Altima 2007-2012 Service Manual: Body control system

System Description


• BCM (body control module) 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.

• BCM is equipped with the diagnosis function that performs the diagnosis with CONSULT-III and various settings.

CAN communication control

In CAN communication, control units are connected with 2 communication lines (CAN-L, CAN-H) allowing a high rate of information transmission with less wiring. Each control unit transmits/receives the data but selectively reads required information only.

CAN communication signal

Refer to the LAN-25, "CAN Communication Signal Chart".

BCM control function list

Component Parts Location

1. BCM M16, M17, M18, M19, M20, M21 (view with instrument panel removed) (coupe shown, sedan similar)

    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 is a c ...

    Other materials:

    ECU diagnosis
    BCM (BODY CONTROL MODULE) Reference Value VALUES ON THE DIAGNOSIS TOOL Terminal Layout Physical Values 1: Sedan only 2: With LH front window anti-pinch 3: With LH and RH front window anti-pinch 4: With Intelligent Key 5: Without Intelligent ...

    Front door speaker
    Removal and Installation REMOVAL 1. Remove the front door finisher. Refer to INT-12, "Removal and Installation" (coupe) and INT-34, "Removal and Installation" (sedan). 2. Remove the front door speaker screws (A), then disconnect the front door speaker connector and remo ...

    Electric ignition system
    System Diagram System Description INPUT/OUTPUT SIGNAL CHART *1: This signal is sent to the ECM through CAN communication line. *2: ECM determines the start signal status by the signals of engine speed and battery voltage. SYSTEM DESCRIPTION Firing order: 1 - 3 - 4 - 2 The ignition t ...