Toyota Venza manuals

Toyota Venza: Lost Communication with AFS LIN (B124D)

Toyota Venza Service Manual / Lighting (ext) / Lighting System / Lost Communication with AFS LIN (B124D)

DESCRIPTION

The DTC is stored when the main body ECU (driver side junction block assembly) detects malfunctions in the LIN communication system.

DTC No.

DTC Detection Condition

Trouble Area

B124D

Malfunction in LIN communication system

  • Inner rear view mirror assembly
  • Harness or connector
  • AFS ECU (headlight swivel ECU assembly)

WIRING DIAGRAM


CAUTION / NOTICE / HINT

NOTICE:

First perform the communication function inspections in How to Proceed with Troubleshooting to confirm that there are no CAN communication malfunctions before troubleshooting this symptom.

PROCEDURE

1.

CHECK FOR DTC

(a) Clear the DTCs (See page ).


(b) Check for DTCs (See page ).


OK:

DTC B124D is not output.


OK

USE SIMULATION METHOD TO CHECK


NG

2.

CHECK HARNESS AND CONNECTOR (AFS ECU - INNER REAR VIEW MIRROR ASSEMBLY)

(a) Disconnect the D44 AFS ECU (headlight swivel ECU assembly) connector.

(b) Disconnect the P12 inner rear view mirror assembly connector.

(c) Measure the resistance according to the value(s) in the table below.

Standard Resistance:

Tester Connection

Condition

Specified Condition

D44-10 (SMR) - P12-3 (LIN)

Always

Below 1 Ω

P12-3 (LIN) - Body ground

Always

10 kΩ or higher


NG

REPAIR OR REPLACE HARNESS OR CONNECTOR


OK

3.

INSPECT AFS ECU (HEADLIGHT SWIVEL ECU ASSEMBLY)

(a) Reconnect the D44 AFS ECU (headlight swivel ECU assembly) connector.

(b) Connect an oscilloscope to the P12 inner rear view mirror assembly connector.


(c) Check the waveform.

OK:

Tester Connection

Tool Setting

Condition

Specified Condition

P12-3 (LIN) - P12-2 (E)

2 V/DIV., 20 ms./DIV.

Ignition switch ON

Correct waveform is as shown

Text in Illustration

*1

Front view of wire harness connector

(to Inner Rear View Mirror Assembly)



OK

REPLACE INNER REAR VIEW MIRROR ASSEMBLY


NG

REPLACE AFS ECU (HEADLIGHT SWIVEL ECU ASSEMBLY)

Automatic High Beam Camera (B124C)
DESCRIPTION The DTC is stored when the main body ECU (driver side junction block assembly) detects malfunctions in the camera (inner rear view mirror assembly). DTC No. DTC D ...

Steering Position Sensor Malfunction (B2414)
DESCRIPTION The AFS ECU (headlight swivel ECU assembly) receives signals indicating the swerve-angle from the steering angle sensor using CAN communication. DTC No. DTC Detec ...

Other materials about Toyota Venza:

Lost Communication with Front Airbag Sensor LH (B1617/84,B1618/84)
DESCRIPTION The front airbag sensor LH circuit consists of the center airbag sensor assembly and front airbag sensor LH. The front airbag sensor LH detects impacts to the vehicle and sends signals to the center airbag sensor assembly to determine if the ...

Operation Check
OPERATION CHECK 1. CHECK AUTO OPERATION NOTICE: Make sure that initialization is completed before inspection (See page ). HINT: When pressing the switch for 0.3 seconds or less, the roof glass moves but auto operation does not operate. (a) Turn the i ...

Installation
INSTALLATION PROCEDURE 1. INSTALL VACUUM SWITCHING VALVE ASSEMBLY (for ACIS) (a) Install the vacuum switching valve assembly (for ACIS) with the bolt. Torque: 9.0 N·m {92 kgf·cm, 80 in·lbf} ...

© 2016-2026 Copyright www.tovenza.com

0.1389