Toyota Tundra Service Manual: Automatic High Beam System (B124B)

Toyota Tundra Service Manual / Vehicle Interior / Lighting / Lighting System / Automatic High Beam System (B124B)

DESCRIPTION

The main body ECU (multiplex network body ECU) determines the status of the automatic high beam system based on the automatic high beam system signal from the forward recognition camera.

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

B124B

Automatic High Beam System

Malfunction in automatic high beam system
  • Forward recognition camera system
  • Pre-collision system
  • SFI system
  • Vehicle stability control system
  • CAN communication system
  • Forward recognition camera
  • Main body ECU (multiplex network body ECU)

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

Click here

HINT:

If the forward recognition camera stores a DTC for a malfunction of any of the following, this DTC will be stored simultaneously.
  • Speed sensor malfunction
  • Yaw rate sensor malfunction
  • Steering sensor malfunction
  • CAN communication system

PROCEDURE

1.

CHECK FOR DTC (HEALTH CHECK)

(a) Connect the Techstream to the DLC3.

(b) Turn the ignition switch to ON.

(c) Turn the Techstream on.

(d) Enter the following menus: System Select / Health Check.

(e) Check for DTCs.

Result

Proceed to

Only DTC B124B is output

A

DTC B124B is output at the same time

B
B

GO TO OTHER DTC CHART
A

2.

CHECK FORWARD RECOGNITION CAMERA

(a) Check if a dynamic radar cruise control system, lane departure alert system and pre-collision system warning message are displayed on the combination meter assembly.

Click here

OK:

No dynamic radar cruise control system, lane departure alert system and pre-collision system warning messages are displayed.

OK

REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU)

NG

GO TO FORWARD RECOGNITION CAMERA SYSTEM

    Automatic High Beam System does not Operate or Operation Indicator does not Illuminate

    Automatic High Beam Camera (B124C)

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