Toyota Tacoma (2015-2018) Service Manual: Front Radar Sensor Incorrect Axial Gap (C1A11)

Toyota Tacoma (2015-2018) Service Manual / Pre-collision / Pre-collision System / Front Radar Sensor Incorrect Axial Gap (C1A11)

DESCRIPTION

When the vehicle is determined to be driving in a straight line or on a gradual curve based on signals from the yaw rate sensor, etc., the millimeter wave radar sensor assembly performs self diagnosis to check if the sensor beam axis has deviated. If the millimeter wave radar sensor assembly beam axis has deviated, the millimeter wave radar sensor assembly detects this and stores DTC C1A11.

DTC No.	Detection Item	DTC Detection Condition	Trouble Area
C1A11	Front Radar Sensor Incorrect Axial Gap	When the ignition switch is ON, misalignment of the millimeter wave radar sensor assembly is detected for approximately 1 second or more.	Millimeter wave radar sensor assembly Wheel alignment

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

PROCEDURE

1.	CHECK VEHICLE CONDITION

(a) Check the operating conditions of the vehicle.

HINT:

DTC C1A11 may be stored if the millimeter wave radar sensor assembly beam axis is temporarily misaligned due to the vehicle being overloaded.

Result	Proceed to
Vehicle is not overloaded or has not been towed	A
Vehicle is overloaded or has been towed	B

GO TO STEP 9

2.	CHECK WHEEL ALIGNMENT

(a) Check the wheel alignment (toe).

Click here HINT:

HINT:

DTC C1A11 may be stored if the millimeter wave radar sensor assembly beam axis is misaligned due to incorrect wheel alignment (toe).

Result	Proceed to
Wheel is misaligned (toe)	A
Wheels are not misaligned (toe)	B

GO TO STEP 6

3.	ADJUST WHEEL ALIGNMENT

(a) Adjust the alignment (toe) of the wheels.

Click here

4.	ADJUST MILLIMETER WAVE RADAR SENSOR ASSEMBLY

(a) Perform millimeter wave radar sensor assembly adjustment.

Click here

5.	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 C1A11 is not output	A
DTC C1A11 is output	B

END

GO TO STEP 7

6.	INSPECT MILLIMETER WAVE RADAR SENSOR ASSEMBLY

(a) Check that the bracket of the millimeter wave radar sensor assembly is not deformed.

HINT:

If the bracket is deformed, replace the millimeter wave radar sensor assembly.

OK:

The bracket is not deformed.

GO TO STEP 4

GO TO STEP 7

7.	REPLACE MILLIMETER WAVE RADAR SENSOR ASSEMBLY

(a) Replace the millimeter wave radar sensor assembly.

Click here (b) Adjust the millimeter wave radar sensor assembly.

(b) Adjust the millimeter wave radar sensor assembly.

Click here

8.	CLEAR DTC (PRE-COLLISION SYSTEM)

(a) Clear the DTCs.

Click here

END

9.	ADJUST MILLIMETER WAVE RADAR SENSOR ASSEMBLY

(a) Return the vehicle to normal.

(b) Perform millimeter wave radar sensor assembly adjustment.

Click here

10.	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 C1A11 is not output	A
DTC C1A11 is output	B

END (MILLIMETER WAVE RADAR SENSOR ASSEMBLY WAS MISALIGNED DUE TO THE VEHICLE BEING OVERLOADED OR TOWED)

11.	CHECK WHEEL ALIGNMENT

(a) Check the wheel alignment (toe).

Click here HINT:

HINT:

DTC C1A11 may be stored if the millimeter wave radar sensor assembly beam axis is misaligned due to incorrect wheel alignment (toe).

Result	Proceed to
Wheel is misaligned (toe)	A
Wheels are not misaligned (toe)	B

GO TO STEP 3

GO TO STEP 7

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