Toyota Tacoma (2015-2018) Service Manual: Yaw Rate Sensor Circuit (C1AA4,C1AA5)

Toyota Tacoma (2015-2018) Service Manual / Cruise Control / Lane Departure Alert System / Yaw Rate Sensor Circuit (C1AA4,C1AA5)

DESCRIPTION

The forward recognition camera receives vehicle stability signals from the yaw rate and acceleration sensor (airbag sensor assembly). If the yaw rate and acceleration sensor (airbag sensor assembly) detects an abnormal yaw rate sensor signal or yaw rate sensor assembly power supply voltage, it informs the forward recognition camera via CAN communication, and DTC C1AA4 or C1AA5 is stored.

DTC No.	Detection Item	DTC Detection Condition	Trouble Area
C1AA4	Yaw Rate Sensor Circuit	3 seconds after the ignition switch is turned to ON, the vehicle speed is 5 km/h (3 mph) or more and a signal from the yaw rate sensor indicating a malfunction in the yaw rate sensor is detected by the forward recognition camera for 5 seconds or more.	Vehicle stability control system Yaw rate and acceleration sensor (airbag sensor assembly) Forward recognition camera
C1AA5	Yaw Rate Sensor Power Supply Voltage Circuit	3 seconds after the ignition switch is turned to ON, the vehicle speed is 5 km/h (3 mph) or more and a signal from the yaw rate sensor indicating an abnormal yaw rate sensor power supply voltage signal is detected by the forward recognition camera for 5 seconds or more.	Vehicle stability control system Yaw rate and acceleration sensor (airbag sensor assembly) Forward recognition camera

CAUTION / NOTICE / HINT

NOTICE:

When replacing the forward recognition camera, always replace it with a new one. If a forward recognition camera which was installed to another vehicle is used, the information stored in the forward recognition camera will not match the information from the vehicle. As a result, a DTC may be stored.
If the forward recognition camera has been replaced with a new one, be sure to perform forward recognition camera learning.
Click here
First check the CAN communication system by following How to Proceed with Troubleshooting. After checking that there are no malfunctions in the CAN communication system, proceed with troubleshooting.
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PROCEDURE

1.	CHECK DTC OUTPUT (VEHICLE STABILITY CONTROL SYSTEM)

HINT:

If the yaw rate and acceleration sensor (airbag sensor assembly) is malfunctioning, DTCs for the vehicle stability control system will be stored. Troubleshoot the vehicle stability control system first.

(a) Connect the Techstream to the DLC3.

(b) Turn the ignition switch to ON.

(d) Check for DTCs.

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

GO TO VEHICLE STABILITY CONTROL SYSTEM

2.	CHECK DTC OUTPUT

(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 following procedure is not performed, the previously output DTC cannot be detected.

(g) Check for DTCs.

Click here

Result	Proceed to
DTC C1AA4 or C1AA5 is output.	A
DTC C1AA4 and C1AA5 are not output.	B

USE SIMULATION METHOD TO CHECK

3.	REPLACE FORWARD RECOGNITION CAMERA

(a) Replace the forward recognition camera.

Click here (b) Adjust the forward recognition camera.

(b) Adjust the forward recognition camera.

Click here

4.	CHECK DTC OUTPUT

(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 following procedure is not performed, the previously output DTC cannot be detected.

(g) Check for DTCs.

Click here

Result	Proceed to
DTC C1AA4 or C1AA5 is output.	A
DTC C1AA4 and C1AA5 are not output.	B

REPLACE YAW RATE AND ACCELERATION SENSOR (AIRBAG SENSOR ASSEMBLY)

END (FORWARD RECOGNITION CAMERA WAS DEFECTIVE)

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