Hyundai Tucson: ESC Bleeding of Brake System

Hyundai Tucson - Fourth generation (NX4) - (2020-2023) - Workshop Manual / Brake System / General Information / ESC Bleeding of Brake System

This procedure should be followed to ensure adequate bleeding of air and filling of the ESC unit, brake lines and master cylinder with brake fluid.

  1. Connect the brake fluid filler to the reservoir tank.


  • Do not reuse the drained fluid.
  • Always use genuine DOT4 brake Fluid.

    Using a non-genuine DOT4 brake fluid can cause corrosion and decrease the life of the system.

  • Make sure no dirt or other foreign matter is allowed to contaminate the brake fluid.
  • Do not spill brake fluid on the vehicle, it may damage the paint; if brake fluid does contact the paint, wash it off immediately with water.
  • The reservoir on the master cylinder must be at the MAX (upper) level mark at the start of bleeding procedure and checked after bleeding each brake caliper. Add fluid as required.
  1. Connect the self-diagnosis to the data link connector located underneath the dash panel.
  2. Connect a clear plastic mbe to the wheel cylinder bleeder plug and insert the other end of the mbe into a half filled clear plastic bottle.
  3. Connect the self-diagnosis S to the data link connector located underneath the dash panel.
  4. Select the "HCU Air Bleeding Mode".

  1. When HCU is operated forcibly, keep the wheel bleeder screw (A) with opened state.


Tightening torque : 6.8 - 12.7 N.m (0.7 - 1.3 kgf.m, 5.0 - 9.4 lb-ft)



Tightening torque : 6.8 - 12.7 N.m (0.7 - 1.3 kgf.m, 5.0 - 9.4 lb-ft)



The bleed screw opens and closes only a quarter of a turn.

  1. Depress the brake pedal with strong force at regular intervals while HCU is operated forcibly.

  1. Repeat the above procedure until the air bubbles are completely removed.
  2. When HCU forced operation is completed, send the "work end" signal.

  1. Close the wheel bleeder screw.
  2. Work in the order shown in the figure below.

  1. Refill the master cylinder reservoir to MAX (upper) level line.


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