Toyota Tacoma (2015-2018) Service Manual: Lost Communication with Yaw Rate Sensor Module (U0123,U0126,U0129,U0142,U0155)

Toyota Tacoma (2015-2018) Service Manual / Cruise Control / Lane Departure Alert System / Lost Communication with Yaw Rate Sensor Module (U0123,U0126,U0129,U0142,U0155)

DESCRIPTION

These DTCs are output when a communication malfunction occurs between the sensors and ECUs.

DTC No.	Detection Item	DTC Detection Condition	Trouble Area
U0123	Lost Communication with Yaw Rate Sensor Module	3 seconds after the ignition switch is turned to ON, the vehicle is being driven at 5 km/h (3 mph) or more and a communication error between the yaw rate sensor and the forward recognition camera is detected for approximately 5 seconds or more.	CAN communication system Yaw rate and acceleration sensor (airbag sensor assembly) Forward recognition camera
U0126	Lost Communication With Steering Angle Sensor Module	3 seconds after the ignition switch is turned to ON, a communication error between the spiral cable with sensor sub-assembly and the forward recognition camera is detected for approximately 5 seconds or more.	CAN communication system Spiral cable with sensor sub-assembly Forward recognition camera
U0129	Lost Communication with Brake System Control Module	3 seconds after the ignition switch is turned to ON, a communication error between the skid control ECU (brake actuator assembly) and the forward recognition camera is detected for approximately 5 seconds or more.	CAN communication system Skid control ECU (brake actuator assembly)1 Skid control ECU (master cylinder solenoid)2 Forward recognition camera
U0142	Lost Communication with Body Control Module "B"	3 seconds after the ignition switch is turned to ON, a communication error between the main body ECU (multiplex network body ECU) and the forward recognition camera is detected for approximately 5 seconds or more.	CAN communication system Main body ECU (Multiplex network body ECU) Forward recognition camera
U0155	Lost Communication with Combination Meter	3 seconds after the ignition switch is turned to ON, a communication error between the combination meter assembly and the forward recognition camera is detected for approximately 50 seconds or more.	CAN communication system Combination meter assembly Forward recognition camera

*1: for Vacuum Brake Booster
*2: for Hydraulic Brake Booster

PROCEDURE

1.	CHECK FOR DTCs

(a) Connect the Techstream to the DLC3.

(b) Turn the ignition switch to ON.

(d) Enter the following menus: Chassis / LKA/LDA / Trouble Codes.

(e) Clear the DTCs.

Click here (f) Make sure that the DTC detection conditions are met.

(f) Make sure that the DTC detection conditions are met.

HINT:

If the detection conditions are not met, the system cannot detect the malfunction.

(g) Enter the following menus: Chassis / LKA/LDA / Trouble Codes.

(h) Check the DTCs.

Click here

Result	Proceed to
DTC U0123, U0126, U0129, U0142 and U0155 are not output	A
DTC U0123, U0126, U0129, U0142 or U0155 is output	B

USE SIMULATION METHOD TO CHECK

GO TO CAN COMMUNICATION SYSTEM

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Vehicle Speed Sensor Circuit (C1AA3)

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