Kia Optima Hybrid: AHB(Active Hydraulic Boost) System / Brake Actuation Unit Repair procedures

Removal
1.
Turn ignition switch OFF and disconnect the negative (-) battery cable.
2.
Remove the air duct (A).

3.
Remove air cleaner assembly (B).

4.
Disconnect the brake fluid level switch connector (A), and remove the reservoir cap.

   
Be sure to completely remove foreign substances from around brake fluid reservoir and cap before opening the reservoir cap. If not, it may cause contamination of brake fluid and deterioration in braking performance.
5.
Remove the brake fluid from the reservoir with a syringe.
   
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.
To prevent any dust entering in the reservoir, the reservoir cap should be closed again after removing brake fluid.
6.
Disconnect reservoir hose from the reservoir and IBAU connecter (A).

7.
Disconnect the brake tube from the IBAU by loosening the tube flare nut (B).
   
Before removing the IBAU, high pressure in an accumulator of PSU should be reduced for safety by conducting "High pressure release mode" of GDS connected to TF HEV.

Tighten torque:
13.7 ~ 16.7 N.m (1.4 ~ 1.7 kgf.m, 10.1 ~ 12.3 lb-ft)

8.
Remove the brake pedal assembly. (Refer to the brake system group - brake pedal)
9.
Remove the IBAU mounting nuts (A) and then remove the IBAU.

Tightening torque:
12.7 ~ 15.7 N.m (1.3 ~ 1.6 kgf.m, 9.4 ~ 11.6 lb-ft)

Installation
1.
Installation is the reverse of removal.
2.
Check the brake pedal operation.
3.
After filling the brake fluid in the reservoir, perform the air bleed. (Refer to the Brakde system - Brake Bleeding Procedures)
4.
Conduct calibration after removing the brake pedal assembly. (Refer to the brake pedal - calibration)
Brake Actuation Unit Components and Components Location

Components     IBAU must not be disassembled. 1. ECU2. Reservoir3. Master cylinder Assembley 4. Valve block ...

Pressure Source Unit Components and Components Location

Components     PSU must not be disassembled. 1. Motor connecter2. Bracket3. Block4. Accumulator5. Damper6. Motor ...

Other information:

Kia Optima Hybrid (TF HEV) 2016-2020 Service Manual: ESC OFF Switch Repair procedures


Inspection 1. Turn ignition switch OFF and disconnect the negative (-) battery cable. 2. Remove the crash pad side switch assembly. 3. Check the continuity between the switch terminals as the ESC OFF switch is engaged. ...

Kia Optima Hybrid (TF HEV) 2016-2020 Service Manual: Components and Components Location


Component Location 1. Seat Memory Unit (IMS)2. IMS control switch3. IMS driver power seat control ...

© 2025 Copyright www.koptimatfhev.com