Hyundai Ioniq: Brake System / Troubleshooting

Hyundai Ioniq (AE) 2017-2024 Service Manual / Brake System / Troubleshooting

Troubleshooting

Symptom	Suspect Area	Reference
Lower pedal or spongy pedal	1. Integrated Brake Actuation Unit (Air in)	air·bleed
	2. AHB system (Fluid leaks)	replace
	3. Piston seals in IBAU (Worn or damaged)	replace
Brake drag	1. Brake pedal free play (Minimum)	adjust
	2. Pad or lining (Cracked or distorted)	replace
	3. Piston (Stuck)	replace
	4. Piston (Frozen)	replace
	5. Anchor or Return spring (Inoperative)	replace
	6. Master cylinder (Inoperative)	replace
	7. IBAU (Inoperative)	replace
Brake pull	1. Piston (Sticking)	replace
	2. Pad or lining (Oily)	replace
	3. Piston (Frozen)	replace
	4. Disc (Scored)	replace
	5. Pad or lining (Cracked or distorted)	replace
Hard pedal but brake inefficient	1. Brake system (Fluid leaks)	repair
	2. Brake system (Air in)	air·bleed
	3. Pad or lining (Worn)	replace
	4. Pad or lining (Cracked or distorted)	replace
	5. Rear brake shoe clearance(Out of adjustment)	adjust
	6. Pad or lining (Oily)	replace
	7. Pad or lining (Glazed)	replace
	8. Disc (Scored)	replace
	9. IBAU (Inoperative)	replace
	10. PSU (Inoperative)	replace
Noise from brake	1. Pad or lining (Cracked or distorted)	replace
	2. Installation bolt (Loosen)	adjust
	3. Disc (Scored)	replace
	4. Sliding pin (Worn)	replace
	5. Pad or lining (Dirty)	clean
	6. Pad or lining (Glazed)	replace
	7. Brake pad shim (Damage)	replace
Brake fades	1. Pad or lining (Worn)	replace
Brake fades	2. Master cylinder (Inoperative)	replace
Brake vibration, pulsation	1. Pedal free play	adjust
	2. Master cylinder (Inoperative)	replace
	3. Caliper (Damage)	replace
	4. Master cylinder cap seal	replace
	5. Damaged brake lines	replace
Heavey pedal (Halt)	1. Brake pedal sticking (lack of grease)	repair
Heavey pedal (Halt)	2. IBAU (Inoperative)	replace
Motor sounds and excessive time to braking when consecutive 2 or 3 times pushing brake pedal (In the case of that accumulator pressure increase rate is under 5bar/sec when checking sensor figures of AHB with GDS)	1. AHB system (air in)	air·bleed
	2. PSU (Inoperative)	replace
Excessive noise when pushing brake pedal	1. IBAU/PSU system (air in)	air·bleed

It is not the malfunction of brake when motor sound is noticed with followings.

–	Repeated pushing brake pedal

–	Pushing and releasing brake pedal with power off.

–	Opening a door of driver side

It is not the malfunction of brake while a brake pedal seems inoperative with followings.

–	Noise when pushing brake pedal fast

–	Noise when pushing brake pedal consecutively

Special service tools

Special Service Tools Tool (Number and Name) Illustration Use 09581-2T100Piston expanderSpreading the front and rear disc brake piston...

Brake bleeding procedures

Integrated Electronic Brake (IEB) System Air Bleeding Procedures • Do not reuse the drained fluid.• Always use genuine DOT3 or DOT4 brake Fluid...

Other information:

Hyundai Ioniq (AE) 2017-2024 Service Manual: Inspection

Inspection[Battery Pack Assembly Troubleshooting Chart] • For SOC check, refer to "SOC Inspection"• For voltage check, refer to "Battery Voltage Inspection"• For battery voltage sensing circuit, refer to "Voltage Sensing Circuit Inspection"• For isolation resistance check, refer to "Isolation Resistance Inspection" [SOC Level and Follow-up] SOC Symptom Warning Lamp Follow-up MIL Service Fuel • Normal --- 10 - 15% • Motor torque limite (Acceleration delay)--ON• Refuel and check the SOC againON--• Repair the MIL or Service Lamp related system• Charge the battery by starting the engine• Refuel if necessary ONON--ON-OnONON 5 - 10% • EV Mode inhibited • FATC Inhibited • LDC Inhibited --ON• Refuel and check the SOC againON--• Repair the MIL or Service Lamp related system• Charge the battery by starting the engine • Refuel if necessaryONON--ON-ONONON 0 - 5% • Impossible to start ON--• Repair the MIL or Service Lamp related system• Start the engine with GDS to charge the battery• Refuel if necessary ONON--ON-ONONON 0% ON--• Repair the MIL or Service Lamp related system• If necessary, Replace Battery Pack• Refuel if necessary [SOC Inspection]1...

Hyundai Ioniq (AE) 2017-2024 Owner's Manual: Speedometer, Tachometer

Speedometer ■ Type A ■ Type B • ECO mode selected ■ Type B • SPORT mode selected The speedometer indicates the speed of the vehicle and is calibrated in miles per hour (MPH) and/or kilometers per hour (km/h). The speedometer for cluster type B is displayed differently according to the mode selected, ECO or SPORT...