VEHICLE STABILITY CONTROL SYSTEM, Diagnostic DTC:C1476, C1477, C1479

DTC Code DTC Name
C1476 Brake Booster Pressure Sensor Circuit Low
C1477 Brake Booster Pressure Sensor Circuit High
C1479 Abnormal Power Supply Voltage in Brake Booster Pressure Sensor

DESCRIPTION

Brake booster pressure sensor (vacuum sensor) detects the pressure in the brake booster.

If a malfunction is detected in the brake booster pressure sensor (vacuum sensor), the fail-safe function prohibits ABS, brake assist, TRC and VSC, and turns the warning and slip indicator lights on.

Tech Tips

EBD control will continue to the extent that EBD control is possible even after ABS is prohibited.

DTC No. Detection Item DTC Detection Condition Trouble Area Note
C1476 Brake Booster Pressure Sensor Circuit Low The brake booster pressure sensor input voltage is less than 0.7 V for 1.2 seconds or more.

  • Wire harness or connector

  • Vacuum booster pressure sensor (vacuum sensor)

  • Skid control ECU (brake actuator assembly)

 for 2AR-FE
C1477 Brake Booster Pressure Sensor Circuit High The brake booster pressure sensor input voltage is more than 4.2 V for 1.2 seconds or more.

  • Wire harness or connector

  • Vacuum booster pressure sensor (vacuum sensor)

  • Skid control ECU (brake actuator assembly)

 for 2AR-FE
C1479 Abnormal Power Supply Voltage in Brake Booster Pressure Sensor The brake booster pressure sensor power supply voltage is more than 5.2 V or less than 4.8 V for 1.2 seconds or more.

  • Wire harness or connector

  • Vacuum booster pressure sensor (vacuum sensor)

  • Skid control ECU (brake actuator assembly)

 for 2AR-FE

WIRING DIAGRAM

B006LVIE04

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. CHECK HARNESS AND CONNECTOR (BRAKE ACTUATOR ASSEMBLY - VACUUM BOOSTER PRESSURE SENSOR (VACUUM SENSOR))


    1. Make sure that there is no looseness at the locking part and the connecting part of the connectors.

    2. Disconnect the A50 skid control ECU (brake actuator assembly) connector.

    3. Disconnect the A51 vacuum booster pressure sensor (vacuum sensor) connector.

    4. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      A50-20 (VSM) - A51-3 (VC) Always Below 1 Ω
      A50-20 (VSM) or A51-3 (VC) - Body ground Always 10 kΩ or higher
      A50-34 (VSI1) - A51-2 (PB) Always Below 1 Ω
      A50-34 (VSI1) or A51-2 (PB) - Body ground Always 10 kΩ or higher
      A50-21 (VSG) - A51-1 (E2) Always Below 1 Ω
      A50-21 (VSG) or A51-1 (E2) - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  2. INSPECT BRAKE ACTUATOR ASSEMBLY (SENSOR POWER SUPPLY OUTPUT)


    1. B006LEYC01
      *a

      Front view of wire harness connector

      (to Vacuum Booster Pressure Sensor (Vacuum Sensor))

      Reconnect the A50 skid control ECU (brake actuator assembly) connector.

    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage
      Tester Connection Condition Specified Condition
      A51-3 (VC) - A51-1 (E2) Engine switch on (IG) 4.75 to 5.25 V
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE VACUUM BOOSTER PRESSURE SENSOR (VACUUM SENSOR) Click here

    NG

    REPLACE BRAKE ACTUATOR ASSEMBLY Click here