DTC    C1271    Low Output Signal of Front Speed Sensor RH (Test Mode DTC)

DTC    C1272    Low Output Signal of Front Speed Sensor LH (Test Mode DTC)

DTC    C1275    Abnormal Change in Output Signal of Front Speed Sensor RH (Test Mode DTC)

DTC    C1276    Abnormal Change in Output Signal of Front Speed Sensor LH (Test Mode DTC)

for Preparation Click here


DESCRIPTION

DTCs C1271 to C1276 will be cleared when the speed sensor sends a vehicle speed signal or when Test Mode ends. DTCs from C1271 to C1276 are output only in Test Mode.

DTC Code
DTC Detection Condition
Trouble Area
C1271
C1272
Detected only during Test Mode.
  1. Front speed sensor RH/LH
  2. Sensor installation
  3. Speed sensor rotor
C1275
C1276
Detected only during Test Mode.
Speed sensor rotor

HINT:
  1. DTCs C1271 and C1275 are for the front speed sensor RH.
  2. DTCs C1272 and C1276 are for the front speed sensor LH.

WIRING DIAGRAM

Refer to DTCs C1401 and C1402 (Click here).

INSPECTION PROCEDURE

NOTICE:
When replacing the brake actuator assembly, perform zero point calibration (Click here).
1.CHECK HARNESS AND CONNECTOR (MOMENTARY INTERRUPTION)

  1. Using the intelligent tester, check for any momentary interruption in the wire harness and connector corresponding to the DTC (Click here).

    ABS/VSC/TRC: 
    Tester Display
    		Measurement Item/Range
    		Normal Condition
    		Diagnostic Note
    FR Speed Open
    		FR speed sensor open detection / ERROR or NORMAL
    		ERROR: Momentary interruption
    NORMAL: Normal
    		-
    FL Speed Open
    		FL speed sensor open detection / ERROR or NORMAL
    		ERROR: Momentary interruption
    NORMAL: Normal
    		-

    Result:
    Result
    		Proceed to
    There are momentary interruptions.
    		A
    There are no momentary interruptions.
    		B
    There is a constant open circuit.
    		C

    HINT:
    Perform the above inspection before removing the sensor and connector.


B
Go to step 4

C
Go to step 6
A


2.REPAIR OR REPLACE HARNESS OR CONNECTOR (SKID CONTROL ECU - FRONT SPEED SENSOR)

  1. Turn the ignition switch off.

  1. Repair or replace the harness or connector.

  1. Check for any momentary interruption between the skid control ECU and the front speed sensor (Click here).

  1. Check that there are no momentary interruptions.


NEXT


3.PERFORM TEST MODE (SIGNAL CHECK)

  1. Turn the ignition switch off.

  1. Perform the sensor check in the Test Mode procedure (Click here).

    OK:
    All Test Mode DTCs are cleared.


NG
Go to step 4
OK

END 

4.READ VALUE USING INTELLIGENT TESTER (FR/FL WHEEL SPEED)

  1. Turn the ignition switch off.

  1. Connect the intelligent tester to the DLC3.

  1. Start the engine.

  1. Select the Data List mode on the intelligent tester (Click here).

    ABS/VSC/TRC: 
    Tester Display
    		Measurement Item/Range
    		Normal Condition
    		Diagnostic Note
    FR Wheel Speed
    		FR wheel speed sensor reading / min.: 0 km/h (0 mph), max.: 326.4 km/h (202.8 mph)
    		Actual wheel speed
    		Similar to speed indicated on the speedometer
    FL Wheel Speed
    		FL wheel speed sensor reading /min.: 0 km/h (0 mph), max.: 326.4 km/h (202.8 mph)
    		Actual wheel speed
    		Similar to speed indicated on the speedometer

  1. Check that there is no difference between the speed value output from the speed sensor displayed on the intelligent tester and the speed value displayed on the speedometer when driving the vehicle.

    HINT:
    Factors that affect the indicated vehicle speed include tire size, tire inflation, and tire wear. The speed indicated on the speedometer has an allowable margin of error. This can be tested using a speedometer tester (calibrated chassis dynamometer). For details about testing and the margin of error, see the reference chart (Click here).

    OK:
    The speed value output from the speed sensor displayed on the intelligent tester is the same as the actual vehicle speed measured using a speedometer tester (calibrated chassis dynamometer).


NG
Go to step 6
OK


5.PERFORM TEST MODE (SIGNAL CHECK)

  1. Turn the ignition switch off.

  1. Perform the sensor check in the Test Mode procedure (Click here).

    OK:
    All Test Mode DTCs are cleared.


NG
Go to step 6
OK

CHECK FOR INTERMITTENT PROBLEMS (SYMPTOM SIMULATION) (Click here)  

6.CHECK FRONT SPEED SENSOR INSTALLATION


    C144929E16

  1. Turn the ignition switch off.

  1. Check the speed sensor installation (Click here).

    OK:
    There is no clearance between the sensor and the front steering knuckle.
    The installation bolt is tightened properly.
    Torque:
    8.5 N*m (87 kgf*cm, 75 in.*lbf)


NG
INSTALL FRONT SPEED SENSOR CORRECTLY (Click here)
OK


7.CHECK FRONT SPEED SENSOR TIP

  1. Remove the front speed sensor (Click here).

  1. Check the speed sensor tip.

    OK:
    No scratches, oil, or foreign matter on the sensor tip.

    NOTICE:
    Check the speed sensor signal after cleaning or replacement (Click here).


NG
CLEAN OR REPLACE FRONT SPEED SENSOR
OK


8.CHECK FRONT SPEED SENSOR ROTOR

  1. Remove the front axle hub sub-assembly (Click here).

  1. Check the speed sensor rotor.

    OK:
    No scratches, oil, or foreign matter on the rotors.

    NOTICE:
    Check the speed sensor signal after cleaning or replacement (Click here).

    HINT:
    If the speed sensor rotor needs to be replaced, replace it together with the front axle hub sub-assembly.


NG
CLEAN OR REPLACE FRONT SPEED SENSOR ROTOR (FRONT AXLE HUB SUB-ASSEMBLY)
OK


9.INSPECT FRONT SPEED SENSOR


    C194310E02

  1. Install the front speed sensor and front axle hub sub-assembly.

  1. Make sure that there is no looseness in the locking part and connecting part of the connector.

  1. Disconnect the front speed sensor connector.

  1. Measure the resistance according to the value(s) in the table below.

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    1 - Body ground
    		Always
    		10 kΩ or higher
    2 - Body ground
    		Always
    		10 kΩ or higher

    NOTICE:
    Check the speed sensor signal after replacement (Click here).


NG
REPLACE FRONT SPEED SENSOR (Click here)
OK


10.CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU - FRONT SPEED SENSOR)


    C194311E02

  1. Make sure that there is no looseness in the locking part and connecting part of the connector.

  1. Disconnect the skid control ECU connector.

  1. Measure the resistance according to the value(s) in the table below.

    Standard Resistance:
    for RH:
    Tester Connection
    		Condition
    		Specified Condition
    A67-7 (FR+) - A62-1
    		Always
    		Below 1 Ω
    A67-7 (FR+) - Body ground
    		Always
    		10 kΩ or higher
    A67-6 (FR-) - A62-2
    		Always
    		Below 1 Ω
    A67-6 (FR-) - Body ground
    		Always
    		10 kΩ or higher
    for LH:
    Tester Connection
    		Condition
    		Specified Condition
    A67-19 (FL+) - A61-1
    		Always
    		Below 1 Ω
    A67-19 (FL+) - Body ground
    		Always
    		10 kΩ or higher
    A67-18 (FL-) - A61-2
    		Always
    		Below 1 Ω
    A67-18 (FL-) - Body ground
    		Always
    		10 kΩ or higher


NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


11.INSPECT SKID CONTROL ECU (SENSOR INPUT)


    C194312E02

  1. Reconnect the skid control ECU connector.

  1. Turn the ignition switch to ON.

  1. Measure the voltage according to the value(s) in the table below.

    Standard Voltage:
    for RH:
    Tester Connection
    		Switch Condition
    		Specified Condition
    A62-1 - Body ground
    		Ignition switch ON
    		8 to 14 V
    for LH:
    Tester Connection
    		Switch Condition
    		Specified Condition
    A61-1 - Body ground
    		Ignition switch ON
    		8 to 14 V


NG
REPLACE BRAKE ACTUATOR ASSEMBLY (Click here)
OK


12.PERFORM TEST MODE (SIGNAL CHECK)

  1. Turn the ignition switch off.

  1. Perform the sensor check in the Test Mode procedure (Click here).

    OK:
    All Test Mode DTCs are cleared.


NG
Go to step 13
OK

CHECK FOR INTERMITTENT PROBLEMS (SYMPTOM SIMULATION) (Click here)  

13.REPLACE FRONT SPEED SENSOR

  1. Turn the ignition switch off.

  1. Replace the front speed sensor (Click here).

    NOTICE:
    Check the speed sensor signal after replacement (Click here).

NEXT


14.PERFORM TEST MODE (SIGNAL CHECK)

  1. Perform the sensor check in the Test Mode procedure (Click here).

    OK:
    All Test Mode DTCs are cleared.


NG
Go to step 15
OK

END 

15.REPLACE FRONT SPEED SENSOR ROTOR

  1. Turn the ignition switch off.

  1. Replace the front axle hub sub-assembly (front speed sensor rotor) (Click here).

    HINT:
    If the speed sensor rotor needs to be replaced, replace it together with the front axle hub sub-assembly.

    NOTICE:
    Check the speed sensor signal after replacement (Click here).

NEXT


16.PERFORM TEST MODE (SIGNAL CHECK)

  1. Perform the sensor check in the Test Mode procedure (Click here).

    OK:
    All Test Mode DTCs are cleared.


NG
REPLACE BRAKE ACTUATOR ASSEMBLY (Click here)
OK

END