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

Toyota Tacoma 2015-2018 Service Manual / Cruise Control / Forward Recognition Camera 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 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	After the ignition switch is turned to ON for 3 seconds or more, when the vehicle is being driven at a speed of 1 km/h or 1 mph or more, a signal from the yaw rate and acceleration sensor (airbag sensor assembly) 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	After the ignition switch is turned to ON for 3 seconds or more, when the vehicle is being driven at a speed of 1 km/h or 1 mph or more, a signal from the yaw rate and acceleration sensor (airbag sensor assembly) 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 Axis Adjustment.
Click here
The forward recognition camera 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:

Forward recognition camera system DTC C1AA4 or C1AA5 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 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 FOR DTCs (FORWARD RECOGNITION CAMERA 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 conditions are not met, the system cannot detect the malfunction.

Click here

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

USE SIMULATION METHOD TO CHECK

3.	REPLACE FORWARD RECOGNITION CAMERA

(a) Replace the forward recognition camera.

Click here (b) Perform forward recognition camera axis adjustment.

(b) Perform forward recognition camera axis adjustment.

Click here

4.	CHECK FOR DTCs (FORWARD RECOGNITION CAMERA 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 conditions are not met, the system cannot detect the malfunction.

Click here

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

END (FORWARD RECOGNITION CAMERA WAS DEFECTIVE)

REPLACE YAW RATE AND ACCELERATION SENSOR (AIRBAG SENSOR ASSEMBLY)

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