LIGHTING SYSTEM, Diagnostic DTC:B124D, B2432

DTC Code	DTC Name
B124D	Lost Communication with AFS LIN
B2432	Lost Communication with Automatic High Beam Sensor

DESCRIPTION

DTC B124D is stored when the main body ECU detects malfunctions in the LIN communication system.
DTC B2432 is stored when the AFS ECU detects malfunctions in the LIN communication system.

DTC Code	DTC Detection Condition	Trouble Area
B124D	Malfunction in LIN communication system	Inner rear view mirror Harness or connector AFS ECU (headlight swivel ECU)
B2432	Malfunction in LIN communication system	Inner rear view mirror Harness or connector AFS ECU (headlight swivel ECU)

WIRING DIAGRAM

INSPECTION PROCEDURE

Note

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

CHECK FOR DTC
1. Clear the DTCs Click here.
2. Check for DTCs Click here.
  
  OK
  
  DTC B124D or B2432 is not output.
NG
CHECK HARNESS AND CONNECTOR (AFS ECU - INNER REAR VIEW MIRROR) Click here

OK

USE SIMULATION METHOD TO CHECK Click here

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

Disconnect the E91 ECU connector.
Disconnect the R13 mirror connector.

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

Standard Resistance

Tester Connection	Condition	Specified Condition
E91-11 (RH+) - R13-10 (LIN)	Always	Below 1 Ω
E91-11 (RH+) - Body ground	Always	10 kΩ or higher

REPAIR OR REPLACE HARNESS OR CONNECTOR

CHECK INNER REAR VIEW MIRROR

Temporarily replace the inner rear view mirror with a new or normally functioning one Click here.

Check for DTCs Click here.

OK
DTC B124D or B2432 is not output.

Result
Result	Proceed to
OK	A
NG (for LHD)	B
NG (for RHD)	C

REPLACE AFS ECU (HEADLIGHT SWIVEL ECU) Click here

END (INNER REAR VIEW MIRROR WAS DEFECTIVE)