Toyota 4Runner: Lost Communication with Front Satellite Sensor Bus (B161A/8A)

DESCRIPTION

The front collision sensor circuit (front airbag sensor RH circuit and front airbag sensor LH circuit) is composed of the center airbag sensor assembly, front airbag sensor RH and front airbag sensor LH.

The front airbag sensor RH or front airbag sensor LH detects impacts to the vehicle and sends signals to the center airbag sensor assembly to determine if the airbag should be deployed.

DTC B161A/8A is stored when a malfunction is detected in the front collision sensor circuit (front airbag sensor RH circuit and front airbag sensor LH circuit).

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

When disconnecting the cable from the negative (-) battery terminal while performing repairs, some systems need to be initialized after the cable is reconnected (See page ).

PROCEDURE

(a) Turn the ignition switch to ON, and wait for at least 60 seconds.

(b) Turn the ignition switch off.

HINT:

If a communication error occurs, DTCs for both the LH and RH sides will be stored simultaneously. To identify the malfunctioning area, turn the ignition switch off and then to ON again.

(c) Turn the ignition switch to ON, and wait for at least 60 seconds.

(d) Check for DTCs (See page ).

B

GO TO DTC B1613/83

C

GO TO DTC B1618/84

A

(a) Turn the ignition switch to ON, and wait for at least 60 seconds.

(b) Clear the DTCs stored in memory (See page
).

(c) Turn the ignition switch off.

(d) Turn the ignition switch to ON, and wait for at least 60 seconds.

(e) Check for DTCs (See page ).

OK:

DTC B161A is not output.

HINT:

Codes other than DTC B161A may be output at this time, but they are not related to this check.

OK

USE SIMULATION METHOD TO CHECK

NG

REPLACE CENTER AIRBAG SENSOR ASSEMBLY