C1402

BRAKE CONTROL: ANTI-LOCK BRAKE SYSTEM (for Hatchback): C1401: Front Speed Sensor RH Malfunction

DTC C1401 - Front Speed Sensor RH Malfunction

DTC C1402 - Front Speed Sensor LH Malfunction

DESCRIPTION

The speed sensors detect the wheel speeds and send appropriate signals to the skid control ECU. Speed sensor rotors have rows of alternating N and S magnetic poles, and their magnetic fields change as the rotors turn.
The speed sensors detect those magnetic changes and send pulse signals to the skid control ECU. The ECU monitors the wheel speeds through these pulse signals to control the ABS control system.









HINT:
- DTCs C1271 and C1272 are output only in the Test Mode.
- DTCs C1271 and C1272 can be deleted when the speed sensor sends a vehicle speed signal or the Test Mode ends.
- DTCs C1401 and C1271 are for the front speed sensor RH.
- DTCs C1402 and C1272 are for the front speed sensor LH.

INSPECTION PROCEDURE

PROCEDURE

1. CHECK FRONT SPEED SENSOR INSTALLATION




(a) Turn the ignition switch off.
(b) 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
10 N*m (105 kgf*cm, 8 ft.*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 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. INSPECT FRONT SPEED SENSOR ROTOR
(a) Check the front speed sensor rotor.
HINT: The front speed sensor rotor is incorporated into the front axle hub bearing.

OK:
No scratches, oil, or foreign matter on the rotors.
NOTE: Check the speed sensor signal after cleaning or replacement Test Mode Procedure.

NG -- CLEAN OR REPLACE FRONT SPEED SENSOR ROTOR
OK -- Continue to next step.
4. REPLACE FRONT SPEED SENSOR
(a) Turn the ignition switch off.
(b) Replace the front speed sensor Removal.
NOTE: Check the speed sensor signal after cleaning or replacement Test Mode Procedure.

NEXT -- Continue to next step.
5. RECONFIRM DTC
(a) Clear the DTC ABS (Antilock Brake System) (for Hatchback).
(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 ABS (Antilock Brake System) (for Hatchback).

Result





B -- END
A -- Continue to next step.
6. REPLACE FRONT AXLE HUB BEARING
(a) Turn the ignition switch off.
(b) Replace the front axle hub bearing Disassembly.
HINT: The front speed sensor rotor is incorporated into the front axle hub bearing.
CAUTION: Check the speed sensor signal after replacement Test Mode Procedure.

NEXT -- Continue to next step.
7. RECONFIRM DTC
(a) Clear the DTC ABS (Antilock Brake System) (for Hatchback).
(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 ABS (Antilock Brake System) (for Hatchback).

Result





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.

B -- REPLACE BRAKE ACTUATOR ASSEMBLY
A -- END