Dtc C1401 Front Speed Sensor Rh Malfunction


DESCRIPTION

INSPECTION PROCEDURE

CHECK FRONT SPEED SENSOR INSTALLATION

INSPECT FRONT SPEED SENSOR TIP

INSPECT FRONT SKID CONTROL ROTOR

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

REPLACE FRONT SPEED SENSOR

RECONFIRM DTC

DTC C1401 Front Speed Sensor RH Malfunction

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 C1402 Front Speed Sensor LH Malfunction


DESCRIPTION

The speed sensors detect the wheel speeds and send appropriate signals to the skid control ECU (brake actuator assembly). The speed sensor has a magnet behind its detection terminal, and detects changes in magnetic flux density between the peaks and valleys of the magnetic rotor teeth.
The speed sensors detect those magnetic changes and send pulse signals to the skid control ECU (brake actuator assembly). The ECU monitors the wheel speeds through these pulse signals to control the brake control system.
HINT:
When the connectors between the speed sensor and skid control ECU (brake actuator assembly) are connected, the following waveform is output.

Toyota Fortuner. Ggn50, 60 Kun51, 61 Tgn51 Lan50.Brake Control.Vehicle Stability Control System. Dtc C1401 Front Speed Sensor Rh Malfunction


DTC Code
DTC Detection Condition
Trouble Area
C1401
C1402
One of the following conditions is met:
  1. At a vehicle speed of 10 km/h (6 mph) or more, the output voltage from one of the speed sensors is below that of the other sensors for 15 seconds or more.
  2. At a vehicle speed of less than 10 km/h (6 mph), the output from one of the speed sensors is 0 km/h (0 mph) for 1 second or more.
  3. At a vehicle speed of 10 km/h (6 mph) or more, the outputs from both front speed sensors are 0 km/h (0 mph) for 15 seconds or more.
  1. Front speed sensor RH/LH
  2. Front skid control rotor RH/LH
  3. Sensor installation
C1271
C1272
Stored during Test Mode.
  1. Front speed sensor RH/LH
  2. Front skid control rotor RH/LH
  3. Sensor installation
HINT:
  1. DTCs C1401 and C1271 are for the front speed sensor RH.
  2. DTCs C1402 and C1272 are for the front speed sensor LH.

INSPECTION PROCEDURE

NOTICE:
Check the speed sensor signal after cleaning or replacement (Toyota Fortuner RM000000XHT08TX.html).
1.CHECK FRONT SPEED SENSOR INSTALLATION

  1. Turn the ignition switch off.



    Toyota Fortuner. Ggn50, 60 Kun51, 61 Tgn51 Lan50.Brake Control.Vehicle Stability Control System. Dtc C1401 Front Speed Sensor Rh Malfunction

  1. Check the speed sensor installation (Toyota Fortuner RM0000010JM029X.html).

    Text in Illustration
    *1
    		Front Speed Sensor
    *a
    		No clearance
    *b
    		CORRECT
    *c
    		INCORRECT
    OK:
    There is no clearance between the sensor and the steering knuckle.
    The installation bolt is tightened properly.


NG
INSTALL FRONT SPEED SENSOR CORRECTLY (Toyota Fortuner RM0000010JM029X.html)
OK


2.INSPECT FRONT SPEED SENSOR TIP

  1. Turn the ignition switch off.

  1. Remove the front speed sensor (Toyota Fortuner RM0000010JP01RX.html).

  1. Check the speed sensor tip.

    OK:
    No scratches, oil or foreign matter on the sensor tip.
    NOTICE:
    Do not replace the speed sensor if no damage to the speed sensor tip is found.
    HINT:
    1. If the sensor is contaminated with oil or other foreign material, clean the sensor.
    2. If there is iron powder sticking to the rotor, this will result in a malfunction. Therefore, confirm that the rotor is not contaminated with foreign material before replacing the sensor.


NG
CLEAN OR REPLACE FRONT SPEED SENSOR
OK


3.INSPECT FRONT SKID CONTROL ROTOR

  1. Turn the ignition switch off.

  1. Remove the front skid control rotor (Toyota Fortuner RM00000112M005X.html).

  1. Check the front skid control rotor.

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


NG
CLEAN OR REPLACE FRONT SKID CONTROL ROTOR
OK


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. Turn the intelligent tester on.

  1. Enter the following menus: Chassis / ABS/VSC/TRC / Data List, and then drive the vehicle.

    ABS/VSC/TRC
    Tester Display
    		Measurement Item/Range
    		Normal Condition
    		Diagnostic Note
    FR Wheel Speed
    		Front speed sensor RH reading / Min.: 0 km/h (0 mph), Max.: 326 km/h (202 mph)
    		Actual wheel speed
    		No large fluctuations when driving at a constant speed.
    FL Wheel Speed
    		Front speed sensor LH reading / Min.: 0 km/h (0 mph), Max.: 326 km/h (202 mph)
    		Actual wheel speed
    		No large fluctuations when driving at a constant speed.

  1. Check the speed value output from the speed sensor displayed on the intelligent tester.

    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, refer to the reference chart (Toyota Fortuner RM0000011JB00WX.html).
    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 5
OK

USE SIMULATION METHOD TO CHECK (Toyota Fortuner RM0000012Q9013X.html)

5.REPLACE FRONT SPEED SENSOR

  1. Turn the ignition switch off.

  1. Replace the front speed sensor (Toyota Fortuner RM0000010JP01RX.html).


NEXT


6.RECONFIRM DTC

  1. Clear the DTCs (Toyota Fortuner RM000000XHV0C7X.html).

  1. Turn the ignition switch off.

  1. Start the engine.

  1. Drive the vehicle at a speed of 40 km/h (25 mph) or more for at least 60 seconds.

  1. Check if the same DTC is output (Toyota Fortuner RM000000XHV0C7X.html).

    Result
    Result
    		Proceed to
    DTC is not output
    		A
    DTC is output
    		B


B
REPLACE FRONT SKID CONTROL ROTOR (Toyota Fortuner RM00000112M005X.html)
A

END