C1401

BRAKE CONTROL: VEHICLE STABILITY CONTROL SYSTEM: C1401,C1402: Front Speed Sensor RH Malfunction

DTC C1401 - Front Speed Sensor RH Malfunction

DTC C1402 - Front Speed Sensor LH Malfunction

DESCRIPTION

The speed sensor detects wheel speed and sends the appropriate signals to the skid control ECU. These signals are used for ABS control.
Speed sensor rotors have rows of alternating N and S magnetic poles, and their magnetic fields change when the rotors turn.
Each speed sensor detects that magnetic change and sends a pulse signal to the skid control ECU.









HINT:
- DTC C1401 is for the front speed sensor RH.
- DTC C1402 is for the front speed sensor LH.

WIRING DIAGRAM





INSPECTION PROCEDURE

PROCEDURE

1. CHECK FRONT SPEED SENSOR INSTALLATION




(a) Check the speed sensor installation.
OK:
There is no clearance between the sensor and the front steering knuckle.
The installation nut is tightened properly.
Torque
8.0 N*m (82 kgf*cm, 71 in.*lbf)
NG -- INSTALL FRONT SPEED SENSOR CORRECTLY
OK -- Continue to next step.
2. CHECK FRONT SPEED SENSOR TIP
(a) Remove the front speed sensor Removal.
(b) Check the speed sensor tip.
OK:
No scratches, oil, or foreign matter on the sensor tip.
NOTE: Check the speed sensor signal after cleaning or replacement Test Mode Procedure.

NG -- CLEAN OR REPLACE FRONT SPEED SENSOR
OK -- Continue to next step.
3. CHECK FRONT SPEED SENSOR ROTOR
(a) Remove the front speed sensor rotor Removal for 2GR-FE, or Removal for 1AR-FE).
(b) Check the speed sensor rotor.
OK:
No scratches, oil, or foreign matter on the rotors.
NOTE: Check the speed sensor signal after cleaning or replacement Test Mode Procedure.
HINT: If the front speed sensor rotor needs to be replaced, replace it together with the front drive outboard joint shaft assembly.

NG -- CLEAN OR REPLACE FRONT SPEED SENSOR ROTOR
OK -- Continue to next step.
4. READ VALUE ON TECHSTREAM (FRONT SPEED SENSOR)
(a) Install the front speed sensor and the front speed sensor rotor.
(b) Connect Techstream to the DLC3.
(c) Start the engine.
(d) Select the Data List mode on Techstream Data List / Active Test.

ABS / VSC / TRAC:





(e) Check that there is no difference between the speed value output from the speed sensor displayed on Techstream 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 On-Vehicle inspection.

OK:
The speed value output from the speed sensor displayed on Techstream is the same as the actual vehicle speed measured using a speedometer tester (calibrated chassis dynamometer).
HINT: If troubleshooting has been carried out according to the Problem Symptoms Table, refer back to the table and proceed to the next step Problem Symptoms Table.

NG -- REPLACE FRONT SPEED SENSOR
OK -- CHECK FOR INTERMITTENT PROBLEMS (SYMPTOM SIMULATION)
5. REPLACE FRONT SPEED SENSOR
(a) Turn the ignition switch off.
(b) Replace the front speed sensor Removal.
NOTE: Check the speed sensor signal after replacement Test Mode Procedure.

NEXT -- Continue to next step.
6. RECONFIRM DTC
(a) Clear the DTCs Reading and Clearing Diagnostic Trouble Codes.
(b) Start the engine.
(c) Drive the vehicle at a speed of 40 km/h (25 mph) or more for at least 60 seconds.
(d) Check if the same DTC is recorded Reading and Clearing Diagnostic Trouble Codes.
Result:





NOTE: Check the speed sensor signal after replacement Test Mode Procedure.
HINT:
- If the front speed sensor rotor needs to be replaced, replace it together with the front drive outboard joint shaft assembly.
- If troubleshooting has been carried out according to the Problem Symptoms Table, refer back to the table and proceed to the next step Problem Symptoms Table.

B -- REPLACE FRONT SPEED SENSOR ROTOR
A -- END