Toyota Tacoma (2015-2018) Service Manual: Yaw Rate Sensor (C1A46)

Toyota Tacoma (2015-2018) Service Manual / Pre-collision / Pre-collision System / Yaw Rate Sensor (C1A46)

DESCRIPTION

If the millimeter wave radar sensor assembly receives a yaw rate sensor malfunction signal from the yaw rate sensor (airbag sensor assembly) or yaw rate sensor zero point malfunction signal from the skid control ECU (master cylinder solenoid)*1 or skid control ECU (brake actuator assembly)*2, DTC C1A46 will be stored.

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

DTC No.	Detection Item	DTC Detection Condition	Trouble Area
C1A46	Yaw Rate Sensor	While the vehicle is being driven at a speed of 5 km/h (4 mph) or more, the millimeter wave radar sensor assembly receives a yaw rate sensor malfunction signal from the yaw rate sensor for approximately 10 seconds. While the vehicle is being driven at a speed of 5 km/h (4 mph) or more, the millimeter wave radar sensor assembly receives a yaw rate sensor zero point malfunction signal from the skid control ECU (master cylinder solenoid)1 or skid control ECU (brake actuator assembly)2 for approximately 10 seconds.	Vehicle stability control system Millimeter wave radar sensor assembly Yaw rate sensor (Airbag sensor assembly)

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

CAUTION / NOTICE / HINT

NOTICE:

When replacing the millimeter wave radar sensor assembly, always replace it with a new one. If a millimeter wave radar sensor assembly which was installed to another vehicle is used, the information stored in the millimeter wave radar sensor assembly will not match the information from the vehicle. As a result, a DTC may be stored.
If the millimeter wave radar sensor assembly has been replaced, be sure to perform millimeter wave radar sensor assembly adjustment.
Click here
The pre-collision system uses the CAN communication system. First, confirm that there are no malfunctions in the CAN communication system. Refer to How to Proceed with Troubleshooting.
Click here

PROCEDURE

1.	CHECK FOR DTCs (VEHICLE STABILITY CONTROL SYSTEM)

HINT:

Pre-collision system DTC C1A46 may be stored due to a malfunction in the vehicle stability control system. Therefore, it is necessary to check for and troubleshoot vehicle stability control system DTCs first.

(a) Check for DTCs.

for Hydraulic Brake Booster: Click here
for Vacuum Brake Booster: Click here

Result	Proceed to
Vehicle stability control system DTCs are not output	A
Vehicle stability control system DTCs are output (for Hydraulic brake booster)	B
Vehicle stability control system DTCs are output (for Vacuum brake booster)	C

GO TO VEHICLE STABILITY CONTROL SYSTEM

2.	CHECK FOR DTCs (PRE-COLLISION SYSTEM)

(a) Clear the DTCs.

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

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

HINT:

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

Click here

Result	Proceed to
DTC C1A46 is not output	A
DTC C1A46 is output	B

USE SIMULATION METHOD TO CHECK

REPLACE MILLIMETER WAVE RADAR SENSOR ASSEMBLY

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