Toyota Tundra Service Manual: Front Radar Sensor Incorrect Axial Gap (C1A11)

Toyota Tundra Service Manual / Vehicle Interior / 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 been towed

A

Vehicle is overloaded or has been towed

B
B

GO TO STEP 9

A

2.

CHECK WHEEL ALIGNMENT

(a) Check the wheel alignment (toe).

Click here

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
B

GO TO STEP 6

A

3.

ADJUST WHEEL ALIGNMENT

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

Click here

NEXT

4.

ADJUST MILLIMETER WAVE RADAR SENSOR ASSEMBLY

(a) Perform millimeter wave radar sensor assembly adjustment.

Click here

NEXT

5.

CHECK FOR DTCs (PRE-COLLISION SYSTEM)

(a) Clear the DTCs.

Click here

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

HINT:

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

(c) Check for DTCs.

Click here

Result

Proceed to

DTC C1A11 is not output

A

DTC C1A11 is output

B
A

END
B

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.

OK

GO TO STEP 4

NG

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.

Click here

NEXT

8.

CLEAR DTC (PRE-COLLISION SYSTEM)

(a) Clear the DTCs.

Click here

NEXT

END

9.

ADJUST MILLIMETER WAVE RADAR SENSOR ASSEMBLY

(a) Return the vehicle to normal.

(b) Perform millimeter wave radar sensor assembly adjustment.

Click here

NEXT

10.

CHECK FOR DTCs (PRE-COLLISION SYSTEM)

(a) Clear the DTCs.

Click here

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

HINT:

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

(c) Check for DTCs.

Click here

Result

Proceed to

DTC C1A11 is not output

A

DTC C1A11 is output

B
A

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

11.

CHECK WHEEL ALIGNMENT

(a) Check the wheel alignment (toe).

Click here

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
A

GO TO STEP 3

B

GO TO STEP 7

    Front Radar Sensor (C1A10)

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