LEMON Manuals: Even more car manuals for everyone
Home >> Lexus >> 2023 >> NX 250 AWD >> Repair and Diagnosis >> External Pages >> Different car >> Section 6 (Electronically Controlled Brake System - Diagnostic Codes (5 Of 6)) >> ELECTRONICALLY CONTROLLED BRAKE SYSTEM (for HEV Model) >> DTC C143A-7E: ABS Solenoid Control Actuator Stuck On; DTC C143A-7F: ABS Solenoid Control Actuator Stuck Off [11/2021 - ] >> Procedure

DTC C143A-7E: ABS Solenoid Control Actuator Stuck On; DTC C143A-7F: ABS Solenoid Control Actuator Stuck Off [11/2021 - ]: Procedure

WARNING: This page is about a different car, the 2025 Lexus NX 350h, 2024 Lexus NX 350h, 2023 Lexus NX 350h, and 2022 Lexus NX 350h. However, it is still accessible from the selected car via links, so may be relevant.
  1. CHECK HARNESS AND CONNECTOR (+BS TERMINAL) 
    1. Make sure that there is no looseness at the locking part and the connecting part of the connectors.

      OK

      The connector is securely connected.

    2. Disconnect the A38 No. 2 skid control ECU (brake actuator assembly) connector.
    3. Check both the connector case and the terminals for deformation and corrosion.

      OK

      No deformation or corrosion.

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

      Standard Voltage

      Tester Connection Condition Specified Condition
      A38-14 (+BS) - Body ground Always 11 to 14 V

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  2

  2. CHECK HARNESS AND CONNECTOR (GND1 TERMINAL) 
    1. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      A38-1 (GND1) - Body ground 1 minute or more after disconnecting the cable from the negative (-) auxiliary battery terminal Below 1 Ω

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  3

  3. CLEAR DTC 
    1. Reconnect the A38 No. 2 skid control ECU (brake actuator assembly) connector.
    2. Clear the DTCs.

      Chassis > Brake/EPB > Clear DTCs 

    3. Turn the ignition switch off.

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  4

  4. RECONFIRM DTC 
    1. Based on the Freeze Frame Data and interview with the customer, attempt to reproduce the conditions when the malfunction occurred.
    2. Check if the same DTC is output.

      Chassis > Brake/EPB > Trouble Codes 

      HINT: 

      • If a speed signal of 6 km/h (4 mph) or more is input to the No. 2 skid control ECU (brake actuator assembly) with the ignition switch turned to ON and the stop light switch assembly off, the ECU performs self-diagnosis of the solenoid circuit.
      • If the normal system code is output (no DTCs are output), slightly jiggle the connectors, wire harnesses, and fuses of the No. 2 skid control ECU (brake actuator assembly).
      • If any DTCs are output while jiggling a connector or wire harness of the No. 2 skid control ECU (brake actuator assembly), inspect and repair the connector or wire harness.
      • If no DTCs were output when reconfirming DTCs, checking for intermittent problems is necessary because it is suspected that the original DTCs were stored due to the poor connection of a connector terminal.

      Result

      Result Proceed to
      DTCs C143A-7E and C143A-7F are not output. A
      DTCs C143A-7E and/or C143A-7F are output. B

    Result: 

    USE SIMULATION METHOD TO CHECK. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [11/2021 - ] 

    Result: 

    REPLACE BRAKE ACTUATOR ASSEMBLY. Refer to  REMOVAL [11/2021 - ]