VEHICLE STABILITY CONTROL SYSTEM, Diagnostic DTC:C1421, C1423, C1424, C1449

DTC Code DTC Name
C1421 Open or Short in Master Cylinder Pressure Sensor
C1423 Master Cylinder Pressure Sensor Zero Point Low Malfunction
C1424 Master Cylinder Pressure Sensor Output Malfunction
C1449 Master Cylinder Output Value Malfunction

DESCRIPTION

DTC No. Detection Item DTC Detection Condition Trouble Area
C1421 Open or Short in Master Cylinder Pressure Sensor When the IG1 terminal voltage is 9.5 V or more, the PMC terminal voltage is not between 0.26 and 4.47 V for 0.1 seconds or more. Master cylinder pressure sensor (brake actuator assembly)
C1423 Master Cylinder Pressure Sensor Zero Point Low Malfunction The PMC terminal voltage is less than 0.26 V for 5 seconds or more. Master cylinder pressure sensor (brake actuator assembly)
C1424 Master Cylinder Pressure Sensor Output Malfunction

Any of the following is detected:


  • At a vehicle speed of 10 km/h (6 mph) or more, noise occurs in the PMC terminal signal 7 times or more within 5 seconds.

  • When the vehicle speed drops from 40 km/h (25 mph) to 0 km/h (0 mph), the master cylinder pressure does not change by at least 0.048 MPa (0.5 kgf/cm2, 7 psi) 5 times or more.

  • At a vehicle speed of 7 km/h (4 mph) or more, the PMC terminal voltage is between 0.86 and 1.0 V and the master cylinder pressure does not change by at least 0.048 MPa (0.5 kgf/cm2, 7 psi) for 60 seconds or more.

  • At a vehicle speed of 7 km/h (4 mph) or more, the PMC terminal voltage is 1.0 V or more and the master cylinder pressure does not change by at least 0.048 MPa (0.5 kgf/cm2, 7 psi) for 30 seconds or more.

  • At a vehicle speed of 7 km/h or more, the condition that the master cylinder pressure sensor input value is excessively larger than the estimated master cylinder pressure based on the vehicle deceleration speed for 1 second when braking (stop light switch assembly ON) occurs 5 times or more after turning the engine switch on, and this recurs 8 times in a successive manner.

 Master cylinder pressure sensor (brake actuator assembly)
C1449 Master Cylinder Output Value Malfunction The master cylinder pressure sensor is in an invalid state for 0.2 seconds or more when the voltage at terminal IG1 is 8.4 V or higher. Master cylinder pressure sensor (brake actuator assembly)
C1424 DTC Detection Conditions
Vehicle Condition
Pattern 1 Pattern 2 Pattern 3 Pattern 4 Pattern 5
Diagnosis Condition - - - - - -
Malfunction Status At a vehicle speed of 10 km/h (6 mph) or more, noise occurs in the PMC terminal signal 7 times or more within 5 seconds. ○ - - - -

When the vehicle speed drops from 40 km/h (25 mph) to 0 km/h (0 mph), the master cylinder pressure does not change by at least 0.048 MPa (0.5 kgf/cm2, 7 psi) 5 times or more.

 - ○ - - -

At a vehicle speed of 7 km/h (4 mph) or more, the PMC terminal voltage is between 0.86 and 1.0 V and the master cylinder pressure does not change by at least 0.048 MPa (0.5 kgf/cm2, 7 psi)

 - - ○ - -

At a vehicle speed of 7 km/h (4 mph) or more, the PMC terminal voltage is 1.0 V or more and the master cylinder pressure does not change by at least 0.048 MPa (0.5 kgf/cm2, 7 psi)

 - - - ○ -
At a vehicle speed of 7 km/h or more, the condition that the master cylinder pressure sensor input value is excessively larger than the estimated master cylinder pressure based on the vehicle deceleration speed for 1 second when braking(stop light switch assembly ON) occurs 5 times or more after turning the engine switch on, and this recurs 8 times in a successive manner. - - - - ○
Detection Time - - 60 seconds or more. 30 seconds or more. -
Number of Trips 1 trip 1 trip 1 trip 1 trip 1 trip

Tech Tips

DTC will be output when conditions for either of the patterns in the table above are met.

Tech Tips

for C1423 and C1424: Even after the trouble areas are repaired, the ABS warning light will not go off unless the following operations are performed:


  1. Turn the engine switch on (IG).

  2. Keep the vehicle stationary for 5 seconds or more and depress the brake pedal lightly 2 or 3 times.

  3. Drive the vehicle at a vehicle speed of 50 km/h (31 mph) and depress and hold the brake pedal firmly for approximately 3 seconds.

  4. Repeat the above operation 3 times or more and check that the ABS warning light goes off.

  5. Clear the DTCs.

CAUTION / NOTICE / HINT

Note

When replacing the skid control ECU (brake actuator assembly), perform zero point calibration and store system information.

Click here

PROCEDURE


  1. REPLACE BRAKE ACTUATOR ASSEMBLY


    1. Replace the master cylinder pressure sensor (brake actuator assembly).

      for LHD: Click here

      for RHD: Click here

    2. Perform zero point calibration of the yaw rate and acceleration sensor and store system information.

      Click here


      Chassis > ABS/VSC/TRC > Utility
      Tester Display
      Signal Check

    3. Perform the sensor check in Test Mode Procedure.

      Click here


      Chassis > ABS/VSC/TRC > Utility
      Tester Display
      Test Mode
      Result
      Proceed to
      NEXT

    NEXT

    END