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Test Mode Procedure

Fig 1: Identifying Warning And Indicator Lights
GTY140376Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  1. CHECK WARNING LIGHT AND INDICATOR LIGHT 
    1. Release the parking brake pedal.
      WARNING:

      When releasing the parking brake, move the shift lever into the P position to hold the vehicle for safety.

    2. When the ignition switch is turned ON, check that the ABS warning light, brake warning light, VSC OFF indicator light, and slip indicator light turn off after about 3 seconds.

      HINT: 

      • When the parking brake is applied or the level of the brake fluid is low, the brake warning light illuminates.
      • If the ECU stores a DTC, the ABS warning light and VSC OFF indicator light illuminate.
      • When depressing the brake pedal repeatedly, it may turn on the brake warning light and sound the buzzer.
      Trouble Area See procedure
      ABS warning light circuit Refer to ABS Warning Light Circuit
      Brake warning light circuit Refer to Brake Warning Light Circuit
      VSC OFF indicator light circuit Refer to VSC OFF Indicator Light Circuit
      Slip indicator light circuit Refer to Slip Indicator Light Circuit
      Skid control buzzer circuit Refer to Skid Control Buzzer Circuit
    Fig 2: Identifying DLC3 Connector Terminals
    GTY142604Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  2. CHECK SENSOR SIGNAL BY TEST MODE (When not Using Techstream) 
    1. Procedures for test mode:
      1. Turn the ignition switch OFF.
      2. Using SST, connect terminals 12 (TS) and 4 (CG) of the DLC3.
        • SST: 09843-18040 
      3. Check that the steering wheel is in the straight ahead position and move the shift lever to P.
      4. Turn the ignition switch ON.
      5. Fig 3: Identifying ABS Warning Light Or VSV OFF Indicator Light Blinking Pattern
        GTY113900Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      6. Check that the ABS warning light and VSC OFF indicator light blinks as shown in the illustration.

        HINT: 

        If no code appears, check the TS and CG terminal circuit, ABS warning light circuit or VSC OFF indicator light circuit.

        Trouble Area See procedure
        TC and CG terminal circuit Refer to TC and CG Terminal Circuit
        ABS warning light circuit Refer to ABS Warning Light Circuit
        VSC OFF indicator light circuit Refer to VSC OFF Indicator Light Circuit
    2. Check the deceleration sensor.
      1. Create gravitational force (0.2 G or more) on the vehicle through deceleration. Use one of the following methods to decelerate the vehicle in the direction it is moving:
        • Apply the brakes while the vehicle is moving.
        • Drive over a bump.
        • Drive on an incline.
      2. Fig 4: Identifying DLC3 Connector Terminals
        GTY113899Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      3. When the deceleration is 0.2 G or more, check that the ABS warning light illuminates.
    3. Check the master cylinder pressure sensor.
      1. Leave the vehicle in a stationary condition and the brake pedal released for 1 second or more. Then quickly depress the brake pedal with a force of 98 N (10 kgf, 22 lbf) or more for 1 second or more.

        HINT: 

        At this time, the ABS warning light turns on for 3 seconds.

    4. Check the speed sensor.
      1. Drive the vehicle straight forward at the following speeds. Then check the ABS warning light.
        Vehicle Speed Check ABS Warning Light
        3 to 5 km/h (2 to 3 mph) Response of sensors Blinks
        45 km/h (28 mph) or higher Deviations of sensor signal Turns off

        HINT: 

        The sensor signal check may not complete if the vehicle's wheels slip or the steering wheel is turned during this check.

      2. Stop the vehicle.
    5. Fig 5: Identifying DLC3 Connector Terminals
      GTY123234Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    6. Read the DTCs.
      1. Using SST, connect terminals 13 (TC) and 4 (CG) of the DLC3.
        • SST: 09843-18040 
      2. Read the number of blinks of the ABS warning light.

        HINT: 

        • As an example, the blinking patterns for trouble codes 72 and 76 are shown below.
        • The conditions are explained in the Diagnostic Trouble Code chart.
        • For the normal code, the light cycles between ON and OFF at intervals of 0.25 seconds.
        • If more than 1 DTC is detected at the same time, the lowest numbered code will be displayed first.
        Fig 6: ABS Warning Light Blinking Pattern
        GTY128828Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      3. After the check, disconnect SST from terminals 13 (TC) and 4 (CG) of the DLC3.
    7. Fig 7: Checking Yaw Rate Sensor
      GTY139424Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    8. Check the yaw rate sensor.
      1. Move the shift lever to D and drive the vehicle at a speed of approximately 5 km/h (3 mph). Turn the steering wheel either to the left or right 90° or more, and drive the vehicle in a half-circle pattern.
      2. Stop the vehicle and move the shift lever to P. Check that the VSC buzzer sounds for 3 seconds.

        If the VSC buzzer sounds, the sensor check has completed normally.

        If the VSC buzzer does not sound, check the VSC buzzer circuit and check the sensor again. If the VSC buzzer still does not sound, there is a malfunction in the VSC sensor. Check the DTCs.

        HINT: 

        • Drive the vehicle in a half-circle pattern. At the end of the turn, the direction of the vehicle should be within 175° to 185° from its start position.
        • Do not spin the wheels.
    9. Fig 8: Identifying DLC3 Connector Terminals
      GTY123234Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    10. Read the DTCs.
      1. Using SST, connect terminals 13 (TC) and 4 (CG) of the DLC3.
        • SST: 09843-18040 
      2. Read the number of blinks of the VSC OFF indicator light.

        HINT: 

        • As an example, the blinking patterns for trouble codes 72 and 76 are shown below.
        • The conditions are explained in the Diagnostic Trouble Code chart.
        • For the normal code, the light cycles between ON and OFF at intervals of 0.25 seconds.
        • If more than 1 DTC is detected at the same time, the lowest numbered code will be displayed first.
        Fig 9: ABS Warning Light Blinking Pattern
        GTY128828Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      3. After the check, disconnect SST from terminals 13 (TC) and 4 (CG) of the DLC3.
  3. CHECK SENSOR SIGNAL BY TEST MODE (When Using Techstream) 
    1. Procedures for test mode:
      1. Turn the ignition switch OFF.
      2. Check that the shift lever is on P.
      3. Connect the Techstream to the DLC3.
      4. Start the engine.
      5. Select the Test Mode using the Techstream.

        HINT: 

        Refer to the Techstream operator's manual for further details.

      6. Fig 10: Identifying ABS Warning Light Or VSV OFF Indicator Light Blinking Pattern
        GTY113900Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      7. Check that the ABS warning light and VSC OFF indicator light blink.

        HINT: 

        If the ABS warning light and VSC OFF indicator light do not blink, check the ABS warning light circuit and VSC OFF indicator light circuit.

        Trouble Area See procedure
        ABS warning light circuit Refer to ABS Warning Light Circuit
        VSC OFF indicator light circuit Refer to VSC OFF Indicator Light Circuit
      8. Start the engine.
    2. Check the deceleration sensor.
      1. Create gravitational force (0.2 G or more) on the vehicle through deceleration. Use one of the following methods to decelerate the vehicle in the direction it is moving:
        • Apply the brakes while the vehicle is moving.
        • Drive over a bump.
        • Drive on an incline.
      2. When the deceleration is 0.2 G or more, check that the ABS warning light illuminates.
    3. Check the master cylinder pressure sensor.
      1. Leave the vehicle in a stationary condition and the brake pedal released for 1 second or more. Then quickly depress the brake pedal with a force of 98 N (10 kgf, 22 lbf) or more for 1 second or more.

        HINT: 

        At this time, the ABS warning light turns on for 3 seconds.

    4. Check the speed sensor.
      1. Drive the vehicle straight forward at the following speed. Then check the ABS warning light.
        Vehicle Speed Check ABS Warning Light
        3 to 5 km/h (2 to 3 mph) Response of sensors Blinks
        45 km/h (28 mph) or higher Deviations of sensor signal Turns off

        HINT: 

        The sensor signal check may not complete if the vehicle's wheels slip or the steering wheel is turned during this check.

      2. Stop the vehicle.
      3. Read the DTCs.
    5. Fig 11: Checking Yaw Rate Sensor
      GTY139425Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    6. Check the yaw rate sensor.
      1. Move the shift lever to D and drive the vehicle at a speed of approximately 5 km/h (3 mph). Turn the steering wheel either to the left or right 90° or more, and drive the vehicle in a half-circle pattern.
      2. Stop the vehicle and move the shift lever to P. Check that the VSC buzzer sounds for 3 seconds.

        If the VSC buzzer sounds, the sensor check has completed normally.

        If the VSC buzzer does not sound, check the VSC buzzer circuit, and check the sensor again.

        If the skid control buzzer still does not sound, there is a malfunction in the VSC sensor. Check the DTCs.

        HINT: 

        • Drive the vehicle in a half-circle pattern. At the end of the turn, the direction of the vehicle should be within 175° to 185° from its start position.
        • Do not spin the wheels.
      3. Read the DTCs.
    DTC OF ABS SENSOR CHECK FUNCTION:

    Code No. Diagnosis Trouble Area
    C1271/71 Low output voltage in front speed sensor RH
    • Front speed sensor RH
    • Sensor installation
    • Sensor rotor
    C1272/72 Low output voltage in front speed sensor LH
    • Front speed sensor LH
    • Sensor installation
    • Sensor rotor
    C1273/73 Low output voltage in rear speed sensor RH
    • Rear speed sensor RH
    • Sensor installation
    • Sensor rotor
    C1274/74 Low output voltage in rear speed sensor LH
    • Rear speed sensor LH
    • Sensor installation
    • Sensor rotor
    C1275/75 Abnormal change in output voltage of front speed sensor RH Front speed sensor rotor RH
    C1276/76 Abnormal change in output voltage of front speed sensor LH Front speed sensor rotor LH
    C1277/77 Abnormal change in output voltage of rear speed sensor RH Rear speed sensor rotor RH
    C1278/78 Abnormal change in output voltage of rear speed sensor LH Rear speed sensor rotor LH
    C1279/79 Deceleration sensor is faulty
    • Deceleration sensor
    • Sensor installation
    C1281/81 Master cylinder pressure sensor output signal is faulty Master cylinder pressure sensor
    DTC OF VSC SENSOR CHECK FUNCTION:

    Code No. Diagnosis Trouble Area
    C0371/71 Yaw rate sensor output signal malfunction
    • Yaw rate sensor
    • Yaw rate sensor circuit