Toyota Tacoma (2015-2018) Service Manual: Automatic High Beam System (B124B)

Toyota Tacoma (2015-2018) Service Manual / 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 Dynamic radar cruise control system Lane departure alert 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:

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 lost

PROCEDURE

1.	CHECK FOR DTC (HEALTH CHECK)

(a) Connect the Techstream to the DLC3.

(b) Turn the ignition switch to ON.

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

(e) Check for DTCs.

Result

Result	Proceed to
Only DTC B124B is output	A
DTC B124B is output at the same time	B

GO TO OTHER DTC CHART

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:

OK:

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

Proceed to
OK
NG

REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU)

GO TO FORWARD RECOGNITION CAMERA SYSTEM

Diagnostic Trouble Code Chart

DIAGNOSTIC TROUBLE CODE CHART HINT: If a trouble code is displayed during the DTC check, inspect the trouble areas listed for that code. For details of the code, refer to the "See page" ...

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DESCRIPTION The main body ECU (multiplex network body ECU) detects a high beam headlight illumination request signal of the automatic high beam system from the forward recognition camera ...

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