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Test Mode Procedure

  1. CHECK WARNING LIGHT AND INDICATOR LIGHT 
    1. Release the parking brake pedal.
      NOTE: When releasing the parking brake, move the P position switch into the P position to hold the vehicle for safety.

      HINT:

      When the parking brake is applied or the level of the brake fluid is low, the BRAKE warning light comes on.

    2. When the power switch is ON (READY), check that the ABS warning light, VSC warning light, BRAKE warning light, Brake Control warning light and SLIP indicator light come on for approximately 3 seconds.

      HINT:

  2. CHECK SENSOR SIGNAL BY TEST MODE 

    HINT:

    • Set the vehicle in the TEST MODE and perform the following procedures to check operation of the deceleration sensor, master cylinder pressure sensor, speed sensor and yaw rate sensor.
    • Check results are indicated by DTCs output only in the TEST MODE.
    • Perform the following procedures (step 1 to step 5) as a set.
    • When entering the test mode, the skid control ECU records all the test mode codes and clears the codes judged to be normal.
    • During test mode, Enhanced VSC does not operate regardless of whether or not the sensor check result is normal or if there is a malfunction.
    • When the mode returns to the normal mode, all the test mode codes are cleared.
    • The ABS warning light and VSC warning light comes on if the sensor has a malfunction.
    1. Step 1: Procedures for test mode
      1. Turn the power switch OFF.
      2. Connect the intelligent tester (with CAN VIM) to the DLC3.
      3. Check that the steering wheel is in the centered position and move the shift lever to the P position.
      4. Turn the power switch ON (READY).
        Fig 2: Connecting Intelligent Tester To DLC3
        G04474555Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      5. Select the SIGNAL CHECK following the intelligent tester screen.
      6. Check that the ABS warning light and VSC warning light indicates TEST MODE.

        HINT:

        If the ABS warning light and VSC warning light do not blink, inspect the ABS warning light circuit and VSC warning light circuit.

        TROUBLESHOOTING CHART

        Trouble Area See Procedure
        ABS warning light circuit ABS WARNING LIGHT DOES NOT COME ON 
        VSC warning light circuit VSC WARNING LIGHT DOES NOT COME ON 
        Fig 3: ABS Warning Light Blinking Pattern
        G04474563Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      7. Start the engine.
    2. Step 2: Check deceleration sensor
      1. Check that the ABS warning light is blinking in TEST MODE.
      2. Keep the vehicle in the stationary condition on a level surface for 1 second or more.

        HINT:

        The blinking pattern of the ABS warning light and VSC warning light do not change. When the sensor is normal and in the test mode, if the above conditions are met, the check is completed.

    3. Step 3: Check yaw rate sensor
      1. Shift the shift lever to the D range and drive the vehicle at the vehicle speed of approx. 5 km/h (3 mph), turn the steering wheel either to left or right 90° or more, and drive in a half-circle pattern.
        NOTE:
        • The vehicle direction at the end should be 180 +-5 ° or less.
        • While turning do not move the shift lever to the P position. Do not turn the power switch OFF.
          Fig 4: [Turning Steering Wheel In Half-Circle Pattern]
          G04474564Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

        HINT:

        • The turning direction is not important.
        • Turning should be completed within 2.0 seconds. However, it is possible to change the vehicle speed, stop or more backward.
      2. Stop the vehicle and move the shift lever to the P position, check that the skid control buzzer sounds for 3 seconds.

        HINT:

        • If the skid control buzzer sounds, the sensor check is completed normally.
        • If the skid control buzzer does not sound, check the skid control buzzer circuit (see SKID CONTROL BUZZER CIRCUIT  ), then perform the sensor check again.
        • If the skid control buzzer still will not sound, there is a malfunction in the Enhanced VSC sensor, so check the DTC.
        • Drive the vehicle in a half-circle pattern. At the end of the turn, the direction of the vehicle should be within 180 +-5° of its start position.
        • Do not spin the wheels.
    4. Step 4: Check master cylinder pressure sensor
      1. Check that the ABS warning light is blinking in TEST MODE.
      2. Leave the vehicle in a stationary condition and the brake pedal in a free condition for 1 second or more, and quickly depress the brake pedal with a force of 98 N (10 kgf, 22 lbf) or more for 1 second or more.
      3. While the vehicle is stopped, release the brake pedal.
      4. While the vehicle is stopped, quickly depress the brake pedal once or more and check the ABS warning light is lit for 3 seconds.
        Fig 5: ABS Warning Light Blinking Pattern In Test Mode
        G04474565Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

        HINT:

        • While the ABS warning light is lit, maintain the condition a brake pedal load of approximately 98 N or more is applied.
        • During the test mode, the ABS warning light comes on for 3 seconds every time the above pedal operation.
        • If the master cylinder pressure sensor check is not completed, randomly depressing the brake pedal will cause the negative pressure to decrease further and the sensor check will be difficult to be completed.
        • If the negative pressure is insufficient, the master cylinder pressure sensor check may not be completed. In this case, turn the engine idle to make the negative pressure sufficient.
        • Strongly depress the brake pedal when the negative pressure is insufficient. The brake warning light may come on with the fail-safe function.
    5. Step 5: Check speed sensor
      1. Check the ABS warning light is blinking of TEST MODE.
      2. Start the sensor signal check.
      3. Drive the vehicle straight forward. Drive the vehicle at a speed of 45 to 80 km/h (28 to 50 mph) or higher for several seconds and check that the ABS warning light goes off.
        VEHICLE SPEED CHECK

        Vehicle Speed Test Check
        0 to 45 km/h
        (0 to 28 mph)        		 Low speed test Response of sensors
        45 to 80 km/h
        (28 to 50 mph)        		 Middle speed test Deviations of sensor signal
        Fig 6: ABS Warning Light Blinking Pattern Of Test Mode
        G04474566Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
        NOTE:
        • Before the speed sensor check, the yaw rate sensor, deceleration sensor and master cylinder pressure sensor checks should be completed.
        • Before the speed sensor check, the yaw rate sensor, deceleration sensor and master cylinder pressure sensor checks should be completed.
        • After the warning light goes off, driving at 50 mph (80 km/h) or more will cause the test mode codes to be recorded again, before the speed reaches at 50 mph (80 km/h), decelerate and stop the vehicle.
        • If the sensor check is not completed, the ABS warning light blinks even while driving and the ABS does not operate.

        HINT:

        If the speed sensor check is completed, the ABS warning light does not come on while driving and blinks at test mode when the vehicle stops.

    6. Step 6: Check end of sensor
      1. If the sensor check is completed, the ABS warning light blinks (test mode) when the vehicle stops and the warning light is off when the vehicle is driving.
        NOTE:
        • When the yaw rate sensor, deceleration sensor, speed sensor and master cylinder pressure sensor checks are completed, the sensor check is completed.
        • If the sensor check is not completed, the ABS warning light blinks even while the vehicle is driving and the ABS does not operate.
        • If a DTC is detected during the test mode, the ABS warning light and VSC warning light comes on.
    7. Step 7: Read test mode
      1. Using intelligent tester (with CAN VIM), check the DTCs in the test mode (refer to step 8).
        NOTE:
        • If only the DTCs are displayed, repair the malfunctioning area and clear the DTC. Check if the ABS warning light and VSC warning light are normal.
        • If only the test mode codes are displayed, perform the test mode again.
        • If DTCs or test mode codes are displayed, repair the malfunction area, clear the DTCs and perform the test mode inspection.
          Fig 7: ABS Warning Light Blinking Pattern In Test Mode
          G04474567Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      HINT:

      • The test mode codes and DTCs are displayed.
      • If the ABS is normal, the ABS warning light comes on for 0.25 seconds and goes off for 0.25 seconds repeatedly.
    8. Step 8: DTC of test mode

      DTC of ABS sensor check function 

      DTC CHART

      Code No. Diagnosis Trouble Area
      C1271/71 Low output voltage of right front speed sensor
      • Right front speed sensor
      • Sensor installation
      • Sensor rotor
      C1272/72 Low output voltage of left front speed sensor
      • Left front speed sensor
      • Sensor installation
      • Sensor rotor
      C1273/73 Low output voltage of right rear speed sensor
      • Right rear speed sensor
      • Sensor installation
      • Sensor rotor
      C1274/74 Low output voltage of left rear speed sensor
      • Left rear speed sensor
      • Sensor installation
      • Sensor rotor
      C1275/75 Abnormal change in output voltage of right front speed sensor Right front sensor rotor
      C1276/76 Abnormal change in output voltage of left front speed sensor Left front speed sensor rotor
      C1277/77 Abnormal change in output voltage of right rear speed sensor Right rear sensor rotor
      C1278/78 Abnormal change in output voltage of left rear speed sensor Left rear speed sensor rotor
      C1279/79 Deceleration sensor is faulty
      • Yaw rate (Deceleration) sensor
      • Sensor installation
      C1281/81 Master cylinder pressure sensor output signal is faulty Master cylinder pressure sensor
      C0371/71 Signal malfunction Yaw rate sensor (Deceleration sensor)

      HINT:

      The code in this table are output only in test mode.

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