ELECTRONICALLY CONTROLLED BRAKE SYSTEM INITIALIZATION


  1. DESCRIPTION


    1. Perform initialization and calibration of the linear solenoid valve when the skid control ECU assembly, brake actuator assembly, brake pedal stroke sensor assembly or brake pedal is replaced.

      Follow the procedure to perform initialization.

      Tech Tips


      • If there is a problem with the auxiliary battery (12 V) voltage, initialization and calibration of the linear solenoid valve cannot complete normally. Make sure to check the auxiliary battery voltage before performing initialization and calibration of the linear solenoid valve.

      • If the actuator temperature is high, initialization and calibration of the linear solenoid valve may not complete normally. If so, wait until the temperature decreases and then perform initialization and calibration of the linear solenoid valve.

      • If the power switch is turned off, the brake pedal is depressed or the vehicle speed signal is input while linear solenoid valve offset learning is being performed, learning will be canceled.

      Part to be Replaced Necessary Operation

      • Skid control ECU assembly

      • Brake pedal stroke sensor assembly

      • Brake pedal

      • Yaw rate and acceleration sensor

      1. Clear stored linear solenoid valve calibration data.

      2. Perform initialization and calibration of the linear solenoid valve.
      Brake actuator assembly

      1. Bleed air.

      2. Clear stored linear solenoid valve calibration data.

      3. Perform initialization and calibration of the linear solenoid valve.

  2. PERFORM INITIALIZATION AND CALIBRATION OF LINEAR SOLENOID VALVE (When Using the GTS)

    Tech Tips

    When entering Test Mode, the skid control ECU assembly communicates with the driving support ECU assembly to judge whether the vehicle is equipped with the pre-collision system. Therefore, do not exit Test Mode within 5 seconds of entering Test Mode (w/ Pre-collision System).


    1. Clear the stored linear solenoid valve calibration data.


      1. Turn the power switch off.

      2. Check that the steering wheel is centered.

      3. Check that the shift lever is in P.

      4. Check that the parking brake is applied.

      5. Connect the GTS to the DLC3.

      6. Turn the power switch on (IG).

      7. Turn the GTS on.

      8. Select the skid control ECU assembly to clear the linear solenoid valve calibration data using the GTS. Enter the following menus: Chassis / ABS/VSC/TRC / Utility / Reset Memory.


        Chassis > ABS/VSC/TRC > Utility
        Tester Display
        Reset Memory

    2. Perform initialization and calibration of the linear solenoid valve.


      1. Turn the power switch off.

      2. Check that the steering wheel is centered.

      3. Check that the shift lever is in P.

      4. Check that the parking brake is applied.

      5. Connect the GTS to the DLC3.

      6. Turn the power switch on (IG) with the brake pedal released.

        Note


        • If linear solenoid valve offset learning is performed without turning the power switch on (IG), the learning process may not be completed properly because of insufficient auxiliary battery voltage.

        • When linear solenoid valve offset learning is interrupted, or the learning process is performed with the shift lever not in P, DTC C1345 (Linear Solenoid Valve Offset Learning Undone) will be stored.

      7. Turn the GTS on.

      8. Switch the skid control ECU assembly to Test Mode using the GTS. Enter the following menus: Chassis / ABS/VSC/TRC / Utility / ECB* Utility / Linear Valve Offset.

        *: Electronically Controlled Brake System


        Chassis > ABS/VSC/TRC > Utility
        Tester Display
        ECB Utility

      9. Leave the vehicle stationary without depressing the brake pedal for 1 or 2 minutes.

      10. Check that the interval between blinks of the brake warning light / yellow (minor malfunction) changes from 1 second to 0.25 seconds.

        Tech Tips


        • The time needed to complete initialization and calibration of the linear solenoid valve varies depending on auxiliary battery voltage.

        • The brake warning light / yellow (minor malfunction) blinks at 1 second intervals during initialization and calibration of the linear solenoid valve and then changes to the Test Mode blinking pattern.

        • The brake warning light / yellow (minor malfunction) blinks at 0.25 second intervals if the Test Mode is normal.

        • Do not exit Test Mode within 5 seconds of entering Test Mode. If Test Mode is exited within 5 seconds of entering Test Mode, DTC U1104 may be stored. If DTC U1104 is output after exiting Test Mode, enter Test Mode again, wait at least 5 seconds, then recheck for DTCs (w/ Pre-collision System).

      11. Check that DTC C1345 (Linear Solenoid Valve Offset Learning Undone) which indicates trouble with stroke sensor zero point learning is not output when the brake warning light / yellow (minor malfunction) changes to the Test Mode blinking pattern upon completion of initialization and calibration of the linear solenoid valve.

      12. Perform zero point calibration of the yaw rate and acceleration sensor.

        Click here

      13. Return to normal mode from Test Mode following the GTS directions.

        Tech Tips

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

      14. Turn the power switch off and disconnect the GTS.

  3. PERFORM INITIALIZATION AND CALIBRATION OF LINEAR SOLENOID VALVE (When Using SST Check Wire)

    Tech Tips

    When entering Test Mode, the skid control ECU assembly communicates with the driving support ECU assembly to judge whether the vehicle is equipped with the pre-collision system. Therefore, do not exit Test Mode within 5 seconds of entering Test Mode (w/ Pre-collision System).


    1. Clear the stored linear solenoid valve calibration data.


      1. Turn the power switch off.

      2. Check that the steering wheel is centered.

      3. Check that the shift lever is in P.

      4. Check that the parking brake is applied.

      5. Turn the power switch on (IG) with the brake pedal released.

      6. A0022N8C29
        *a Front view of DLC3

        Using SST, connect and disconnect terminals TS and CG of the DLC3 4 times or more within 8 seconds.

        SST
        09843-18040

      7. Check that no codes other than ABS code 42, VSC code 45 and electronically controlled brake system code 48, 66, or 95 are output by the diagnostic system.

        Tech Tips


        • How to read DTCs:

          Diagnostic trouble codes are represented by the number of blinks of a warning light. For example, code 21 would be shown by 2 blinks, a pause of 1.5 seconds, and then 1 blink.

        • If one code is detected:

          The light repeats the same code after a pause of 4 seconds.

        • If multiple codes are detected:

          The light outputs one code after another with a 2.5-second pause between each code. When all codes have been output, there is a 4-second pause and then the light begins to output the codes again.

        • The ABS warning, brake warning / yellow (minor malfunction) and slip indicator lights do not indicate a normal system code.

    2. Perform initialization and calibration of the linear solenoid valve.


      1. Turn the power switch off.

      2. Check that the steering wheel is centered.

      3. Check that the shift lever is in P.

      4. Check that the parking brake is released.

      5. A0022N8C29
        *a Front view of DLC3

        Using SST, connect terminals TS and CG of the DLC3.

        SST
        09843-18040

      6. Turn the power switch on (IG) with the brake pedal released.

        Note


        • If linear solenoid valve offset learning is performed without turning the power switch on (IG), the learning process may not be completed properly because of insufficient auxiliary battery voltage.

        • When linear solenoid valve offset learning is interrupted, or the learning process is performed with the shift lever not in P, DTC 66 (Linear Solenoid Valve Offset Learning Undone) will be stored.

      7. Leave the vehicle stationary without depressing the brake pedal for 1 or 2 minutes.

      8. Check that the interval between blinks of the brake warning light / yellow (minor malfunction) changes from 1 second to 0.25 seconds.

        Tech Tips


        • The time needed to complete initialization and calibration of the linear solenoid valve varies depending on the auxiliary battery voltage.

        • The brake warning light / yellow (minor malfunction) blinks at 1 second intervals during initialization and calibration of the linear solenoid valve and changes to the Test Mode blinking pattern.

        • The brake warning light / yellow (minor malfunction) blinks at 0.25 second intervals if Test Mode is normal.

        • Do not exit Test Mode within 5 seconds of entering Test Mode. If Test Mode is exited within 5 seconds of entering Test Mode, DTC U1104 may be stored. If DTC U1104 is output after exiting Test Mode, enter Test Mode again, wait at least 5 seconds, then recheck for DTCs (w/ Pre-collision System).

      9. Check that DTC 66 (Linear Solenoid Valve Offset Learning Undone) which indicates trouble with stroke sensor zero point learning is not output when the brake warning light / yellow (minor malfunction) changes to the Test Mode blinking pattern upon completion of initialization and calibration of the linear solenoid valve completion.

      10. Perform zero point calibration of the yaw rate and acceleration sensor.

        Click here

      11. Turn the power switch off and disconnect SST from the DLC3.