BatteryHigh
Traction battery health variation, particularly on ex-private-hire cars
- Typically appears
- Any
- What to inspect
- Run a state-of-health check and review charging history
2016–2022 Hyundai Ioniq · common problems & known faults
Hybrid, plug-in and electric versions of an efficient hatchback, popular with private hire and high-mileage commuters.
Compiled & reviewed by the VehicleFaults Research Team · last reviewed August 2026
Quick answer
The most commonly reported faults on the 2016–2022 Hyundai Ioniq are Traction battery health variation, particularly on ex-private-hire cars, Whining or clicking noise during acceleration or regenerative braking on BEV models and PTC heater failure resulting in no warm air blowing into the cabin when in EV mode. 3 of the documented issues are rated high severity · inspect these first. Full inspection points, onset mileage and what to check are listed below.
Reliability snapshot
Based on the documented faults on this page for the Hyundai Ioniq.
3.9/ 10
- Critical
- 0
- High
- 3
- Medium
- 5
- Low
- 0
Guidance only · reflects reported patterns, not a specific car's condition.
Hyundai Ioniq problems by year
Which faults an average example has usually reached depends on its age. Pick a model year for the faults that matter on that build.
Known faults to check
TransmissionMedium
Dual-clutch hesitation and judder on hybrid models
- Typically appears
- 70,000+ miles
- What to inspect
- Drive in slow traffic from cold
BrakesMedium
Rear disc corrosion from regenerative braking
- Typically appears
- Age-related
- What to inspect
- Inspect the rear discs carefully
ElectricalMedium
12V battery faults causing multiple warning lights
- Typically appears
- Age-related
- What to inspect
- Test the 12V battery before diagnosing anything else
DrivetrainHigh
Whining or clicking noise during acceleration or regenerative braking on BEV models.
- Typically appears
- 30,000-50,000 miles
- What to inspect
- Drive at 20-30 mph, lift off the accelerator to engage regen, and listen for a distinct whine or clicking sound from the front reduction gear.
ElectricalMedium
Charging cable gets stuck in the socket or vehicle refuses to initiate charge.
- Typically appears
- 4-6 years
- What to inspect
- Plug in a Type 2 cable, lock and unlock the car using the key fob, and ensure the cable releases smoothly without needing the manual emergency release in the boot.
HVACHigh
PTC heater failure resulting in no warm air blowing into the cabin when in EV mode.
- Typically appears
- 40,000-70,000 miles
- What to inspect
- Turn on the ignition to Ready mode, set climate control to maximum heat, and check if warm air blows from the vents within 60 seconds.
CoolingMedium
Engine management light illuminated due to active grille air flaps sticking open or closed.
- Typically appears
- 50,000-80,000 miles
- What to inspect
- Shine a torch through the lower front bumper grille to visually check if the plastic louvres are jammed with road debris or visibly broken.
Inspecting a Hyundai Ioniq?
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Check this exact carFrequently asked questions
Are ex-taxi Ioniqs a problem?
Not mechanically, but the interior needs work and the battery needs a documented health check.
Which version is easiest to sell?
The self-charging hybrid. It suits buyers who cannot charge at home.
Does the warranty transfer?
Hyundai's warranty transfers with the car when servicing is up to date, which is a strong selling point.
What are the standard service intervals across the Ioniq range?
Across all powertrains including HEV, PHEV, and BEV, Hyundai specifies a strict service interval of 10,000 miles or 12 months, whichever comes first. Missing this interval by even a minor margin can void the manufacturer warranty. Ensure the service book shows consistent, on-time stamps before retailing the vehicle.
Why is the coolant service on the 38kWh electric model unusually expensive?
The facelifted 38kWh BEV uses a specialised low-conductivity coolant for the high-voltage battery system to prevent electrical shorting. This fluid is significantly more expensive than standard engine coolant and requires a specific bleeding procedure using diagnostic equipment. This mandatory change occurs every 40,000 miles or 3 years.
Which charging cables should be present with PHEV and BEV models?
Plug-in Hybrid and Electric models were originally supplied with two cables: a standard 3-pin domestic charger and a Type 2 to Type 2 cable for public or wallbox charging. Replacing missing genuine Hyundai cables costs over £300, so always verify both are present under the boot floor.
Sources & further reading
Faults are compiled from documented recalls, technical bulletins, owner reports and mechanic sources, then reviewed for accuracy. This is guidance only · not a substitute for a professional inspection.