Dtc C1A11 Front Radar Sensor Incorrect Axial Gap

Vehicle Interior. Land Cruiser. Urj200, 202 Grj200 Vdj200
Pre-Crash Safety. Land Cruiser. Urj200, 202 Grj200 Vdj200

DESCRIPTION

INSPECTION PROCEDURE

CHECK DTC OUTPUT (PRE-CRASH SAFETY SYSTEM)

CHECK VEHICLE CONDITION

CHECK WHEEL ALIGNMENT

ADJUST WHEEL ALIGNMENT

CHECK MILLIMETER WAVE RADAR SENSOR ASSEMBLY

PERFORM MILLIMETER WAVE RADAR SENSOR ASSEMBLY (BEAM AXIS ADJUSTMENT)

CHECK DTC OUTPUT (PRE-CRASH SAFETY SYSTEM)

CLEAR DTC

PERFORM MILLIMETER WAVE RADAR SENSOR ASSEMBLY (BEAM AXIS ADJUSTMENT)

DTC C1A11 Front Radar Sensor Incorrect Axial Gap

DTC C1A14 Front Radar Sensor Beam Axis Not Adjusted


DESCRIPTION

The driving support ECU assembly uses the millimeter wave radar sensor assembly to detect obstacles in front of the vehicle.
Based on this information, the driving support ECU assembly sends pre-crash control operation signals.
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 from the vehicle movement direction. When the millimeter wave radar sensor assembly beam axis has deviated, the driving support ECU assembly detects this, and stores DTC C1A11.
After installing a new millimeter wave radar sensor assembly, if sensor beam axis adjustment is not performed, DTC C1A14 is stored.

DTC No.
DTC Detection Condition
Trouble Area
C1A11
When the engine switch is on (IG), misalignment of the millimeter wave radar sensor assembly is detected for approximately 0.2 seconds.
  1. No. 1 millimeter wave radar sensor bracket
  2. Millimeter wave radar sensor assembly
  3. Driving support ECU assembly
C1A14
When the vehicle is being driven at a speed of 10 km/h (6 mph) or more, misalignment of the millimeter wave radar sensor assembly is detected for approximately 0.2 seconds.
  1. Millimeter wave radar sensor assembly
  2. Driving support ECU assembly

INSPECTION PROCEDURE

NOTICE:
  1. 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.
    1. for LHD: Click here
    2. for RHD: Click here
  2. When replacing the driving support ECU assembly, always replace it with a new one. If a driving support ECU assembly which was installed to another vehicle is used, the information stored in it will not match the information from the vehicle and a DTC may be stored.
  3. When replacing the millimeter wave radar sensor assembly, always replace it with a new one. When a new millimeter wave radar sensor assembly is installed to the vehicle, it receives vehicle information from the driving support ECU assembly and stores it. If a millimeter wave radar sensor assembly which was installed to another vehicle is used, the information stored in the driving support ECU assembly and millimeter wave radar sensor assembly will not match and a DTC may be stored.
  4. When the millimeter wave radar sensor assembly is replaced with a new one, adjustment of the radar sensor beam axis must be performed (Click here).
1.CHECK DTC OUTPUT (PRE-CRASH SAFETY SYSTEM)

  1. Check if the stored DTCs are current DTCs.

  1. Connect the GTS to the DLC3.

  1. Turn the engine switch on (IG).

  1. Turn the GTS on.

  1. Enter the following menus: Body Electrical / Pre-Crash 2 / Trouble Codes.

  1. Check for DTCs (Click here).

Result
Result
Proceed to
Current DTC C1A11 is output
A
Current DTC C1A14 is output
B
History DTC C1A11 is output
C


B
Go to step 6

C
Go to step 8
A


2.CHECK VEHICLE CONDITION

  1. 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
Result
Proceed to
Vehicle is not overloaded or being towed.
A
Vehicle is overloaded or being towed.
B


B
Go to step 9
A


3.CHECK WHEEL ALIGNMENT

  1. Check the front and rear 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
Result
Proceed to
Front or rear wheel is misaligned (toe)
A
Front and rear wheels are not misaligned (toe)
B


B
Go to step 5
A


4.ADJUST WHEEL ALIGNMENT

  1. Adjust the alignment (toe) of the wheels (Click here).


NEXT


5.CHECK MILLIMETER WAVE RADAR SENSOR ASSEMBLY

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

    Result
    Result
    		Proceed to
    Bracket is not deformed
    		A
    No. 1 millimeter wave radar sensor bracket is deformed
    		B
    The other than No. 1 millimeter wave radar sensor bracket is deformed
    		C



B
REPLACE NO. 1 MILLIMETER WAVE RADAR SENSOR BRACKET (Click here)

C
REPLACE DRIVING SUPPORT ECU ASSEMBLY (Click here)
A


6.PERFORM MILLIMETER WAVE RADAR SENSOR ASSEMBLY (BEAM AXIS ADJUSTMENT)

  1. Perform millimeter wave radar sensor assembly adjustment (Click here).


NEXT


7.CHECK DTC OUTPUT (PRE-CRASH SAFETY SYSTEM)

  1. Connect the GTS to the DLC3.

  1. Turn the engine switch on (IG).

  1. Turn the GTS on.

  1. Enter the following menus: Body Electrical / Pre-Crash 2 / Trouble Codes.

  1. Clear the DTCs (Click here).

  1. Make sure that the DTC detection conditions are met.

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

  1. Check for DTCs (Click here).

    HINT:
    After performing the radar sensor beam axis adjustment, if the same DTC is output again after the DTC detection conditions are met, replace the driving support ECU assembly.
Result
Result
Proceed to
DTC C1A11 and C1A14 are not output
A
DTC C1A11 or C1A14 is output
B


B
REPLACE DRIVING SUPPORT ECU ASSEMBLY (Click here)
A

END (MILLIMETER WAVE RADAR SENSOR ASSEMBLY [BEAM AXIS ADJUSTMENT] WAS DEFECTIVE)

8.CLEAR DTC

  1. Check for DTCs related to misalignment of millimeter wave radar sensor assembly.

    HINT:
    If only history DTCs are stored, they may have stored due to a temporarily condition such as overloading of the vehicle, and the system returned to normal when beam axis learning was performed.

  1. Clear the DTCs (Click here).


NEXT

END

9.PERFORM MILLIMETER WAVE RADAR SENSOR ASSEMBLY (BEAM AXIS ADJUSTMENT)

  1. Return the vehicle to normal operating conditions.

  1. Perform millimeter wave radar sensor assembly adjustment (Click here).

  1. Clear the DTCs (Click here).


NEXT

END