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Repair Procedures: Replacement

NOTE:
  • If a DTC occurs in the ECU, check the connectors and wiring. If no problem is found, replace the ECU.
  • Before replacing the MDPS ECU, use the diagnostic device to read the settings of the old ECU.
  1. Perform the "ECU data backup" by KDS following in the order below.
    1. Connect self-diagnosis connector (16 pins) located under the driver side crash pad to self-diagnosis device, and then turn the self-diagnosis device after key is ON.
    2. Select the "vehicle model" and "Motor Driven Power Steering" on KDS vehicle selection screen.
    3. Select the "Part replacement (Power steering ECU)" on KDS screen, then select OK.
      Fig 1: Scantool Display - Vehicle S/W Management
      G12141649Courtesy of KIA MOTORS AMERICA, INC.
    4. Proceed with the test according to the screen instructions.
    Fig 2: Scantool Display - Part Replacement (Power Steering ECU)
    G12141650Courtesy of KIA MOTORS AMERICA, INC.
    Fig 3: Scantool Display - Part Replacement Function (Power Steering ECU)
    G12141651Courtesy of KIA MOTORS AMERICA, INC.
    Fig 4: Scantool Display - Part Replacement Procedures (Power Steering ECU)
    G12141652Courtesy of KIA MOTORS AMERICA, INC.
    Fig 5: Scantool Display - VIN Number
    G12141653Courtesy of KIA MOTORS AMERICA, INC.
    Fig 6: Scantool Display - Information
    G12141654Courtesy of KIA MOTORS AMERICA, INC.
    NOTE: If a DTC occurs in the ECU, check the connectors and wiring. If no problem is found, replace the ECU.
  2. Disconnect the battery negative cable from the battery and then wait for at least 30 seconds.
  3. Remove the crash pad lower panel.

    (Refer to Body - "CRASH PAD LOWER PANEL ")

  4. Disconnect the MDPS ECU connectors (A).
    Fig 7: Locating MDPS ECU Connectors
    G12141655Courtesy of KIA MOTORS AMERICA, INC.
  5. Loosen the mounting bolts (A) and then remove the MDPS ECU (B).

    Tightening torque: 

    19.6 ~ 23.5 N.m (2.0 ~ 2.4 kgf.m, 14.5 ~ 17.3 lb-ft)

    Fig 8: Locating MDPS ECU And Mounting Bolts
    G12141656Courtesy of KIA MOTORS AMERICA, INC.
  6. Loosen the star wrench (A) and then remove the MDPS ECU bracket (B).

    Tightening torque: 

    7.8 ~9.8 N.m (0.8 ~ 1.0 kgf.m, 5.8 ~ 7.2 lb-ft)

    Fig 9: Locating Star Wrench And MDPS ECU Bracket
    G12141657Courtesy of KIA MOTORS AMERICA, INC.
  7. Install in the reverse order of removal.
  8. Perform the "ECU data restore" by KDS following in the order below.
    1. Connect self-diagnosis connector (16 pins) located under the driver side crash pad to self-diagnosis device, and then turn the self-diagnosis device after key is ON.
    2. Select the "vehicle model" and "Motor Driven Power Steering" on KDS vehicle selection screen.
    3. Select the "Part replacement (Power steering ECU)" on KDS screen, then select OK.
      Fig 10: Scantool Display - Vehicle S/W Management
      G12141658Courtesy of KIA MOTORS AMERICA, INC.
    4. Proceed with the test according to the screen instructions.
    Fig 11: Scantool Display - Part Exchange (Power Steering ECU)
    G12141659Courtesy of KIA MOTORS AMERICA, INC.
    Fig 12: Scantool Display - Part Exchange Function (Power Steering ECU)
    G12141660Courtesy of KIA MOTORS AMERICA, INC.
    Fig 13: Scantool Display - Part Exchange Procedures (Power Steering ECU)
    G12141661Courtesy of KIA MOTORS AMERICA, INC.
    Fig 14: Scantool Display - VIN Number
    G12141662Courtesy of KIA MOTORS AMERICA, INC.
    Fig 15: Scantool Display - Information
    G12141663Courtesy of KIA MOTORS AMERICA, INC.
  9. Perform the "STEERING ANGLE SENSOR (SAS) CALIBRATION" AND "SET THE STEERING FEEL TORQUE TO ZERO ".
  10. Turn off the IGN switch and wait for 10 seconds or more. Then check the operation after starting the engine.