VEHICLE STABILITY CONTROL SYSTEM (for Vacuum Brake Booster), Diagnostic DTC:C1421, C1281, C1423, C1424

DTC Code DTC Name
C1421 Open or Short in Master Cylinder Pressure Sensor
C1281 Master Cylinder Pressure Sensor Output Malfunction (Test Mode DTC)
C1423 Master Cylinder Pressure Sensor Zero Point Low Malfunction
C1424 Master Cylinder Pressure Sensor Output Malfunction

DESCRIPTION

The master cylinder pressure sensor is connected to the skid control ECU in the brake actuator assembly.

A01DNR7E19
DTC Code DTC Detection Condition Trouble Area
C1421

Either condition is met:


  1. With the IG1 terminal voltage between 9.5 and 17.4 V, the VCM terminal voltage is not between 4.4 and 5.6 V for 1.2 seconds or more.

  2. When the VCM terminal voltage is between 4.8 and 5.2 V, the PMC terminal voltage is not between 0.19 and 4.57 V for 1.2 seconds or more.

Brake actuator assembly (Master cylinder pressure sensor)
C1281 Stored only during test mode. Brake actuator assembly (Master cylinder pressure sensor)
C1423 The PMC terminal voltage is below 0.27 V for 5 seconds or more. Brake actuator assembly (Master cylinder pressure sensor)
C1424

One of the following conditions is met:


  1. Noise occurs in the PMC terminal signal 7 times or more within 5 seconds.

  2. When the vehicle speed drops from 40 km/h (25 mph) to 10 km/h (6 mph), the master cylinder pressure does not change by at least 0.048 MPa.

  3. At a vehicle speed of 7 km/h (4.3 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 for 60 seconds or more.

  4. 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 for 30 seconds or more.

  5. At a vehicle speed of 7 km/h (4 mph) or more with the stop switch on, a state in which the pressure sensor input value is sufficiently more than the estimated master pressure continues for 1 second or more and this state occurs 5 or more times each time the ignition switch is turned to ON, and this occurs 8 or more times consecutively.

Brake actuator assembly (Master cylinder pressure sensor)

WIRING DIAGRAM

Refer to DTC C1425 Click here.

INSPECTION PROCEDURE

Note

When replacing the brake actuator assembly, perform calibration Click here.

PROCEDURE


  1. REPLACE BRAKE ACTUATOR ASSEMBLY


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


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