Hyundai Tucson: ESC Control unit (HECU)

Hyundai Tucson - Fourth generation (NX4) - (2020-2023) - Workshop Manual / Brake System / ESC (Electronic Stability Control) System / ESC Control unit (HECU)


  1. Front - right (FR)
  2. Rear - left (RL)
  3. Rear - right (RR)
  4. Front - left (FL)
  5. MC2
  6. MCI
  7. ESC Control unit (HECU) connector
  8. Bracket

ESC Control unit (HECU)- Removal


  1. Disconnect the battery negative ( - ) terminal.
  2. Remove the glow relay unit assembly. U 1.6 (Refer to Engine Electrical System - "Glow Relay Unit Assembly")
  3. Pull up the lock of the ESC control unit (HECU) connector and then disconnect the connector (A).

  1. Separate the brake mbe by removing the flare nuts (A), (B) connected to the ESC control unit (HECU).

Tightening torque :

(A): 13.7 - 16.7 N m (1.4 - 1.7 kgfrn. 10.1 - 12.3 lb ft)

(B) : 18.6 - 22.6 N m (1.9 - 2.3 kgfrn, 13.7 - 16.6 lb ft)

  1. Remove the bracket mounting nuts and remove the ESC control unit (HECU) (A) from the vehicle.

Tightening torque : 16.7 - 25.5 N m (1.7 - 2.6 kgfm, 12.3 - 18.8 lb ft)

  1. Remove the bolts to remove the bracket (B) from the ESC control unit (HECU) (A).



  1. Install in the reverse order of removal.
  2. After installation, bleed the brake system.

    (Refer to Brake System - "Brake Bleeding Procedures")

  3. Conduct the Variant Coding.
  4. Conduct the Auto Detected Sensor Calibration.
  5. Conduct the Longitudinal G Sensor Calibration.
  6. After replacing the ESC control unit execute the "Assembly Check (ECU replacement)" of the additional function to check that the mounting is successful.


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