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Inspection Procedure

NOTE: When replacing the ABS and TRACTION actuator assembly, perform zero point calibration (see CALIBRATION ).
  1. INSPECT SKID CONTROL ECU (GND2 TERMINAL) 
    1. Disconnect the skid control ECU connector.
    2. Measure the resistance according to the value(s) in the table below.

      Resistance 

      TESTER CONNECTION SPECIFIED CONDITION REFERENCE CHART

      Tester Connection Specified Condition
      A44-1 (GND2) - Body ground Below 1 Ω
    Fig 1: Identifying Skid Control ECU Connector Terminals
    G05296949Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (GND2 CIRCUIT) 

    OK: Go to next step 

  2. PERFORM ACTIVE TEST BY INTELLIGENT TESTER (ABS MOTOR RELAY) 
    1. Connect the intelligent tester to the DLC3.
    2. Start the engine.
    3. Select the ACTIVE TEST mode on the intelligent tester.
    4. Check the operating sound of the ABS motor relay and motor when operating it with the intelligent tester.

    ACTIVE TEST: ABS/VSC 

    ACTIVE TEST: ABS/VSC REFERENCE CHART

    Item Vehicle Condition / Test Details Diagnostic Note
    MOTOR RELAY Turns ABS motor relay ON or OFF Operating sound of relay (clicking sound) and motor can be heard

    OK: 

    The operating sound of the ABS motor relay and motor is heard. 

    NG: REPLACE ABS AND TRACTION ACTUATOR ASSEMBLY 

    OK: Go to next step 

  3. RECONFIRM DTC 
    1. Clear the DTC (see DTC CHECK / CLEAR ).
    2. Start the engine.
    3. Drive the vehicle at the speed of 4.3 mph (7 km/h) or more.
    4. Check that the same DTC is recorded (see DTC CHECK / CLEAR ).

      HINT:

      Reinstall the sensors, connectors, etc. and restore the vehicle to its prior condition before rechecking for DTCs.

    Result 

    RESULT CHART

    Display (DTC Output) Proceed To
    DTC (C1251/51) is not output A
    DTC (C1251/51) is output B

    HINT:

    • If a speed signal of 4 mph (6 km/h) or more is input to the skid control ECU, with the engine switch on (IG) and the stop light switch off, the ECU performs self diagnosis of the motor and solenoid circuits.
    • If a normal system code is output (trouble code is not output), slightly jiggle the connectors, wire harness, and fuses of the ABS and TRACTION actuator assembly. Make sure that no DTCs are output.
    • If any DTCs are output while jiggling a connector or wire harness of the ABS and TRACTION actuator assembly, inspect and repair the connector or wire harness.
    • It is suspected that the DTCs were output due to bad connection of the connector terminal.

    B: REPLACE ABS AND TRACTION ACTUATOR ASSEMBLY 

    A: END 

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