Hyundai Tucson: ESC Control unit (HECU) - Adjustment

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


Perform diagnostic procedure by using diagnostic device as shown below :

  1. Connect self-diagnosis connector (16pins) located under the driver side crash pad to self-diagnosis device, and then torn the self-diagnosis device after key is ON.
  2. Select the "vehicle model" and "ABS/ESC" on diagnostic tool vehicle selection screen, then select OK.

Variant Code Reset

Variant Coding

Variant Coding

Longitudinal G Sensor Calibration

Longitudinal G Sensor Calibration

Assembly Check (ECU replacement)

Assembly Check (ECU replacement)



  1. The ESC OFF switch is for the user to turn off the ESC system.
  2. The ESC OFF lamp is on when ESC OFF switch is engaged.


  1. Disconnect the battery negative ( - ) terminal.
  2. Remove the crash pad lower panel.

    (Refer to Body - "Crash Pad Lower Panel")

  3. Remove the screws and remove the ESC OFF switch (A).

  1. Remove the ESC OFF switch connector (A) by pressing the locking pin.



  1. Install in the reverse order of removal


     Front wheel speed sensor/ Front wheel speed sensor connector

    Components Front wheel speed sensor Front wheel speed sensor connector Removal Loosen the wheel nuts slightly. Raise the vehicle, and make sure it is securely supported. Remove the front wheel and tire (A) from the front hub.

     Rear wheel speed sensor

    Components 2WD Rear wheel speed sensor 4WD Rear wheel speed sensor Rear wheel speed sensor- Removal- 2WD Removal 2WD Loosen the wheel nuts slightly. Raise the vehicle, and make sure it is securely supported. Remove th

     Rear wheel speed sensor- Replacement

    Replacement Remove the rear wheel hub bearing assembly. (Refer to Drivesliaft and Axle - "Rear Hub - Carrier") Fix the rear hub bearing assembly (A) on the vise. WARNING When fixing on the vise, use a cloth not to be damaged


     Gear actuator assembly

    Components Gear actuator assembly Specification Connector and Terminal Function Circuit Diagram Removal Turn ignition switch OFF and disconnect the negative (-) battery cable. Remove the air cleaner assembly and ai

     Input shaft speed sensor- Installation

    Installation Check that the shaft is in the "N" position. Install the position sensor (A) and then lightly tighten the bolts. Install the position sensor "N" fixing SST(No.:09430-2Cl 10). Tighten position