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Test Mode Procedure

  1. WARNING LIGHT AND INDICATOR LIGHT INITIAL CHECK 
    1. Release the parking brake.
      NOTE:

      Before releasing the parking brake, move the shift lever to P for safety (for automatic transmission) or set the chocks to hold the vehicle for safety (for manual transmission).

      HINT: 

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

    2. When the engine switch is turned on (IG), check that the ABS warning, brake warning, VSC OFF indicator and slip indicator lights all come on and the TR(A)C OFF message will be displayed on the multi-information display for approximately 3 seconds.
      Fig 1: Identifying ABS Warning Light, Brake Warning Light, VSC OFF Indicator Light, & Slip Indicator Light
      GTY149310Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      HINT: 

      • If the skid control ECU stores any DTCs, the ABS warning and slip indicator lights will come on.
      • If any of the indicators remain on or do not come on, proceed to troubleshooting for the light circuits listed below.
      Trouble Area See Procedure
      ABS warning light circuit (Remains on) Refer to ABS Warning Light Remains ON
      ABS warning light circuit (Does not come on) Refer to ABS Warning Light does not Come ON
      Brake warning light circuit (Remains on) Refer to Brake Warning Light Remains ON
      Brake warning light circuit (Does not come on) Refer to Brake Warning Light does not Come ON
      Multi-information display (TR(A)C OFF indicator) circuit (Remains on) Refer to TRAC OFF Indicator Light Remains ON
      Multi-information display (TR(A)C OFF indicator) circuit (Does not come on) Refer to TRAC OFF Indicator Light does not Come ON
      VSC OFF indicator light circuit (Remains on) Refer to VSC OFF Indicator Light Remains ON
      VSC OFF indicator light circuit (Does not come on) Refer to VSC OFF Indicator Light does not Come ON
      Slip indicator light circuit (Remains on) Refer to Slip Indicator Light Remains ON
      Slip indicator light circuit (Does not come on) Refer to Slip Indicator Light does not Come ON
  2. SENSOR CHECK USING TEST MODE (SIGNAL CHECK) (When Using the Techstream) 
    NOTE:

    After replacement of the brake actuator assembly and/or yaw rate and acceleration sensor, perform zero point calibration of the yaw rate and acceleration sensor.

    HINT: 

    • If the engine switch is turned from on (IG) to on (ACC) or off during Test Mode (signal check), DTCs recorded during the sensor check will be cleared.
    • During Test Mode (signal check), the skid control ECU records all DTCs detected in the sensor check. By performing Test Mode (signal check), the codes are cleared if a normal condition is confirmed. The remaining codes are the codes where a malfunction was found.
    1. Procedure to enter Test Mode
      1. Turn the engine switch off.
      2. Check that the steering wheel is centered.
      3. Check that the shift lever is in P (for automatic transmission) or the parking brake is applied (for manual transmission).
      4. Connect the Techstream to the DLC3.
      5. Turn the engine switch on (IG).
      6. Turn the Techstream on.
      7. Switch the skid control ECU to Test Mode using the Techstream. Enter the following menus: Chassis / ABS/VSC/TRAC / Utility / Signal Check.
      8. Check that the ABS warning and slip indicator lights come on for several seconds and then blink in Test Mode.
        Fig 2: identifying ABS And VSC OFF Indicator Light Test Mode Blinking Pattern
        GTY100092Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

        HINT: 

        If the ABS warning and slip indicator lights do not blink, inspect the TS and CG terminal circuit and ABS warning and slip indicator light circuits.

      9. Check the ABS sensors.

        HINT: 

        Check that the ABS warning light is blinking in the Test Mode blinking pattern before performing the ABS sensor check.

    2. Lost Booster Pressure Judgement Check and Master Cylinder Pressure Sensor Zero Point Calibration
      NOTE:

      Perform a check in the lost booster pressure state (vacuum in the booster is depressurized).

      1. Turn the engine switch on (IG).
      2. Check that the brake warning light comes on when depressing the brake pedal with a force greater than 59 N (6 kgf, 13.2 lbf) for 1 second or more. (The lost booster pressure state is judged as normal.)
      3. Start the engine while depressing the brake pedal with a force greater than 59 N (6 kgf, 13.2 lbf) for 1 second or more.
      4. Check that the brake warning light goes off when quickly releasing the brake pedal. (The lost booster pressure state is judged as normal.)
      5. Leave the vehicle for 1 second or more. (Master cylinder pressure sensor zero point calibration)
        NOTE:
        • If depressing the brake pedal slowly or repeatedly, the master cylinder pressure sensor zero point calibration is not performed normally.
        • If the lost booster pressure judgement check results are not normal, then the master cylinder pressure sensor check cannot be performed.
        • If rechecking after the engine has started, end Test Mode, enter Test Mode again, and release vacuum in the booster by pumping the brake pedal prior to rechecking.
    3. Acceleration Sensor Check
      1. Keep the vehicle stationary on a level surface for 1 second or more.

        HINT: 

        The acceleration sensor check can be performed with the master cylinder pressure sensor check below.

    4. Master Cylinder Pressure Sensor Check
      1. Leave the vehicle in a stationary condition and release the brake pedal for 1 second or more, then quickly and continuously depress the brake pedal with a force greater than 98 N (10 kgf, 22.0 lbf) for 1 second.
      2. Check that the ABS warning light stays on for 3 seconds.

        HINT: 

        • Confirm that the ABS warning light comes on.
        • While the ABS warning light is illuminated, continue to depress the brake pedal with a force of 98 N (10 kgf, 22.0 lbf) or more.
        • The ABS warning light comes on for 3 seconds every time the brake pedal operation above is performed.
    5. Speed Sensor Check
      1. Drive the vehicle in reverse for more than 1 second at 3 km/h (2 mph) or more (Reverse signal check).
      2. Check that the ABS warning light goes off.

        HINT: 

        Drive the vehicle in reverse and check the speed sensor signal. Note that the signal check cannot be completed if the vehicle speed is 45 km/h (28 mph) or more.

      3. Drive the vehicle straight-ahead.

        Accelerate the vehicle to a speed of 45 km/h (28 mph) or more for several seconds (Forward signal check).

      4. Check that the ABS warning light goes off.

        HINT: 

        • The sensor check may not be completed if wheelspin occurs.
        • The ABS warning light blinks when the sensor check has been completed and the brake pedal is depressed.
        • The ABS warning light comes on immediately if a malfunction is detected during the speed sensor check.
      5. Stop the vehicle.
        NOTE:
        • Before performing the speed sensor check, complete the acceleration sensor and master cylinder pressure sensor checks.
        • The speed sensor check may not be completed if the speed sensor check is started while turning the steering wheel or spinning the wheels.
        • After the ABS warning light goes off, if the vehicle speed exceeds 80 km/h (50 mph), a sensor check code will be stored again. Decelerate or stop the vehicle before the speed reaches 80 km/h (50 mph).
        • If the sensor check has not been completed, the ABS warning light will blink while driving and the ABS will not operate.

        HINT: 

        When the sensor check has been completed, the ABS warning light goes off while driving and blinks in the Test Mode pattern while the vehicle is stationary.

    6. End of Sensor Check
      1. If the sensor check is completed, the ABS warning light blinks (Test Mode) when the vehicle is stopped and goes off while driving the vehicle.
        Fig 3: identifying ABS And VSC OFF Indicator Light Test Mode Blinking Pattern
        GTY100092Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
        NOTE:
        • When the acceleration sensor, speed sensor, and master cylinder pressure sensor checks are completed, the sensor check is completed.
        • If the sensor check has not been completed, the ABS warning light will blink while driving and the ABS will not operate.
    7. Read Sensor Check DTCs
      1. Read the DTC(s) by following the Techstream screen.
        NOTE:
        • If only DTCs other than Test Mode sensor check DTCs are displayed, repair the malfunctions and clear the DTCs.
        • If Test Mode sensor check DTCs and other DTCs are displayed or if only Test Mode sensor check DTCs are displayed, repair the malfunctions, clear the DTCs, and perform Test Mode inspection again.

        HINT: 

        See "Sensor Check DTCs".

      2. Turn the engine switch off and disconnect the Techstream.
    8. Sensor Check DTCs
      ABS SENSOR

      DTC Code Detection Item Trouble Area
      C1270 Initialization Incomplete
      • ECM
      • CAN communication system (Skid control ECU to ECM)
      • Skid control ECU
      C1271 Low Output Signal of Front Speed Sensor RH
      • Front speed sensor RH
      • Sensor installation
      • Speed sensor rotor
      C1272 Low Output Signal of Front Speed Sensor LH
      • Front speed sensor LH
      • Sensor installation
      • Speed sensor rotor
      C1273 Low Output Signal of Rear Speed Sensor RH
      • Rear speed sensor RH
      • Sensor installation
      • Speed sensor rotor
      C1274 Low Output Signal of Rear Speed Sensor LH
      • Rear speed sensor LH
      • Sensor installation
      • Speed sensor rotor
      C1275 Abnormal Change in Output Signal of Front Speed Sensor RH Speed sensor rotor
      C1276 Abnormal Change in Output Signal of Front Speed Sensor LH Speed sensor rotor
      C1277 Abnormal Change in Output Signal of Rear Speed Sensor RH Speed sensor rotor
      C1278 Abnormal Change in Output Signal of Rear Speed Sensor LH Speed sensor rotor
      C1279 Acceleration Sensor Output Voltage Malfunction
      • Sensor installation
      • Yaw rate and acceleration sensor
      C1281 Master Cylinder Pressure Sensor Output Malfunction
      • Stop light switch
      • Brake pedal load sensing switch
      • Master cylinder pressure sensor

      HINT: 

      The codes in this table are output only in Test Mode (signal check).

  3. SENSOR CHECK USING TEST MODE (SIGNAL CHECK) (When not Using the Techstream) 
    NOTE:

    After replacement of the skid control ECU and/or yaw rate and acceleration sensor, perform zero point calibration of the yaw rate and acceleration sensor.

    HINT: 

    • If the engine switch is turned from on (IG) to on (ACC) or off during Test Mode (signal check), DTCs recorded during the sensor check will be cleared.
    • During Test Mode (signal check), the skid control ECU records all DTCs detected in the sensor check. By performing Test Mode (signal check), the codes are cleared if a normal condition is confirmed. The remaining codes are the codes where a malfunction was found.
    1. Procedure to enter Test Mode
      1. Turn the engine switch off.
      2. Check that the steering wheel is centered.
      3. Check that the shift lever is in P (for automatic transmission) or the parking brake is applied (for manual transmission).
      4. Using SST, connect terminals TS and CG of the DLC3.
        Fig 4: Identifying Terminals TS And CG Of DLC3
        GTY108555Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
        • SST: 09843-18040 
      5. Turn the engine switch on (IG).
      6. Check that the ABS warning and slip indicator lights come on for several seconds and then blink in Test Mode.
        Fig 5: identifying ABS And VSC OFF Indicator Light Test Mode Blinking Pattern
        GTY100092Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

        HINT: 

        If the ABS warning and slip indicator lights do not blink, inspect the TS and CG terminal circuit and ABS warning and slip indicator light circuits.

      7. Check the ABS sensors.

        HINT: 

        Check that the ABS warning light is blinking in the Test Mode blinking pattern before performing the ABS sensor check.

    2. Lost Booster Pressure Judgement Check and Master Cylinder Pressure Sensor Zero Point Calibration
      NOTE:

      Perform a check in the lost booster pressure state (vacuum in the booster is depressurized).

      1. Turn the engine switch on (IG).
      2. Check that the brake warning light comes on when depressing the brake pedal with a force greater than 59 N (6 kgf, 13.2 lbf) for 1 second or more. (The lost booster pressure state is judged as normal.)
      3. Start the engine while depressing the brake pedal with a force greater than 59 N (6 kgf, 13.2 lbf) for 1 second or more.
      4. Check that the brake warning light goes off when quickly releasing the brake pedal. (The lost booster pressure state is judged as normal.)
      5. Leave the vehicle for 1 second or more. (Master cylinder pressure sensor zero point calibration)
        NOTE:
        • If depressing the brake pedal slowly or repeatedly, the master cylinder pressure sensor zero point calibration is not performed normally.
        • If the lost booster pressure judgement check results are not normal, then the master cylinder pressure sensor check cannot be performed.
        • If rechecking after the engine has started, end Test Mode, enter Test Mode again, and release vacuum in the booster by pumping the brake pedal prior to rechecking.
    3. Acceleration Sensor Check
      1. Keep the vehicle stationary on a level surface for 1 second or more.

        HINT: 

        The acceleration sensor check can be performed with the master cylinder pressure sensor check below.

    4. Master Cylinder Pressure Sensor Check
      1. Leave the vehicle in a stationary condition and release the brake pedal for 1 second or more, then quickly and continuously depress the brake pedal with a force greater than 98 N (10 kgf, 22.0 lbf) for 1 second.
      2. Check that the ABS warning light stays on for 3 seconds.

        HINT: 

        • Confirm that the ABS warning light comes on.
        • While the ABS warning light is illuminated, continue to depress the brake pedal with a force of 98 N (10 kgf, 22.0 lbf) or more.
        • The ABS warning light comes on for 3 seconds every time the brake pedal operation above is performed.
    5. Speed Sensor Check
      1. Drive the vehicle in reverse for more than 1 second at 3 km/h (2 mph) or more (Reverse signal check).
      2. Check that the ABS warning light goes off.

        HINT: 

        Drive the vehicle in reverse and check the speed sensor signal. Note that the signal check cannot be completed if the vehicle speed is 45 km/h (28 mph) or more.

      3. Drive the vehicle straight-ahead.

        Accelerate the vehicle to a speed of 45 km/h (28 mph) or more for several seconds (Forward signal check).

      4. Check that the ABS warning light goes off.

        HINT: 

        • The sensor check may not be completed if wheelspin occurs.
        • The ABS warning light blinks when the sensor check has been completed and the brake pedal is depressed.
        • The ABS warning light comes on immediately if a malfunction is detected during the speed sensor check.
      5. Stop the vehicle.
        NOTE:
        • Before performing the speed sensor check, complete the acceleration sensor and master cylinder pressure sensor checks.
        • The speed sensor check may not be completed if the speed sensor check is started while turning the steering wheel or spinning the wheels.
        • After the ABS warning light goes off, if the vehicle speed exceeds 80 km/h (50 mph), a sensor check code will be stored again. Decelerate or stop the vehicle before the speed reaches 80 km/h (50 mph).
        • If the sensor check has not been completed, the ABS warning light will blink while driving and the ABS will not operate.

        HINT: 

        When the sensor check has been completed, the ABS warning light goes off while driving and blinks in the Test Mode pattern while the vehicle is stationary.

    6. End of Sensor Check
      1. If the sensor check is completed, the ABS warning light blinks (Test Mode) when the vehicle is stopped and goes off while driving the vehicle.
        Fig 6: Identifying Test Mode Blinking Pattern
        GTY114615Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
        NOTE:
        • When the acceleration sensor, speed sensor, and master cylinder pressure sensor checks are completed, the sensor check is completed.
        • If the sensor check has not been completed, the ABS warning light will blink while driving and the ABS will not operate.
    7. Read Sensor Check DTCs
      1. Using SST, connect terminals TC and CG of the DLC3.
        Fig 7: Identifying Terminals TC And CG Of DLC3
        GTY108556Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
        • SST: 09843-18040 
      2. Count the number of blinks of the ABS warning light.
        Fig 8: Identifying ABS Warning Light And Slip Indicator Lights
        GTY125000Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
        NOTE:
        • If only DTCs other than Test Mode sensor check DTCs are displayed, repair the malfunctions and clear the DTCs.
        • If Test Mode sensor check DTCs and other DTCs are displayed or if only Test Mode sensor check DTCs are displayed, repair the malfunctions, clear the DTCs, and perform Test Mode inspection again.

        HINT: 

        • If more than 1 malfunction is detected at the same time, the lowest numbered code will be displayed first.
        • See "Sensor Check DTCs".
      3. After performing the check, disconnect SST from terminals TS and CG, and TC and CG of the DLC3 and turn the engine switch off.
      4. Turn the engine switch on (IG).

        HINT: 

        • If the engine switch is not turned on (IG) after SST is removed from the DLC3, the previous Test Mode will continue.
        • If the engine switch is turned on (IG) with terminals TS and CG connected, the previous Test Mode will continue.
    8. Sensor Check DTCs
      ABS SENSOR

      DTC Code Detection Item Trouble Area
      71 Low Output Signal of Front Speed Sensor RH
      • Front speed sensor RH
      • Sensor installation
      • Speed sensor rotor
      72 Low Output Signal of Front Speed Sensor LH
      • Front speed sensor LH
      • Sensor installation
      • Speed sensor rotor
      73 Low Output Signal of Rear Speed Sensor RH
      • Rear speed sensor RH
      • Sensor installation
      • Speed sensor rotor
      74 Low Output Signal of Rear Speed Sensor LH
      • Rear speed sensor LH
      • Sensor installation
      • Speed sensor rotor
      75 Abnormal Change in Output Signal of Front Speed Sensor RH Speed sensor rotor
      76 Abnormal Change in Output Signal of Front Speed Sensor LH Speed sensor rotor
      77 Abnormal Change in Output Signal of Rear Speed Sensor RH Speed sensor rotor
      78 Abnormal Change in Output Signal of Rear Speed Sensor LH Speed sensor rotor
      79 Acceleration Sensor Output Voltage Malfunction
      • Sensor installation
      • Yaw rate and acceleration sensor
      81 Master Cylinder Pressure Sensor Output Malfunction
      • Stop light switch
      • Brake pedal load sensing switch
      • Master cylinder pressure sensor
      88 Initialization Incomplete
      • ECM
      • CAN communication system (Skid control ECU to ECM)
      • Skid control ECU

      HINT: 

      The codes in this table are output only in Test Mode (signal check).

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