Hyundai Ioniq 5: common faults & what to check

Which Hyundai Ioniq 5 are you looking at?

2 generation variants documented. Pick the shape you recognise: the faults, the servicing and the timeline below all narrow to it. Free, no account needed.

Electric

2 variants documented

2021–nowNE2021–nowNEEV 58kWhElectricDocumented issues12 knownSee faults & what to checkKickTyres illustration, not a photograph.

2021–nowNE2021–nowNEEV 72.6/77.4kWhElectricDocumented issues12 knownSee faults & what to checkKickTyres illustration, not a photograph.

Now narrow it to the engine

A 1.8 and a 2.4 of the same car do not fail the same way, so the faults below narrow to the engine as well as the year. Free, no account needed.

Start your free check on this Hyundai Ioniq 5

No plate needed. You get the risk score, the buyer's checklist and the guided inspection for the exact car you picked above — not the whole nameplate.

The checks worth doing on a Hyundai Ioniq 5 before you hand over any money. Every documented fault is listed below, each with its own page.

• Serious issue

  Ask the seller for the service history and look for a dealer invoice or service stamp showing recall 21D064 (shift control unit software) was done.

  See why

  Parking pawl software rollaway recall (NE Ioniq 5, 2021-2022)

  The NE Ioniq 5 built for 2021 and 2022 was recalled (Hyundai recall 21D064, REC-005448) because a shift control unit software fault could let the parking pawl fail, so the car could move or roll away while in Park. The fix is a free software update at a Hyundai dealer. Until it is done, use the electric park brake every time the car is parked. Not every car in these years is in the recall; a dealer check of the VIN is the only way to know.

  What you would notice

  • Car creeps or moves while showing Park
  • Shift system warning message

  Typically $0 to put right.

• Costly issue

  Check for any history of stranding events in service records.

  See why

  VCU Software Crash Causing Loss of Ready Mode

  The Vehicle Control Unit on the E-GMP platform contains a firmware defect in early build variants that causes the VCU to enter an unrecoverable error state during the high-voltage system pre-charge sequence. The vehicle powers off normally but on the next start attempt the Ready lamp fails to illuminate, the drivetrain remains inert, and a cascade of BMS and VCU fault codes is stored. The issue is not triggered by any user input and occurs randomly, including after overnight parking. Hyundai issued a mandatory firmware update addressing the pre-charge state machine logic. This is identical in mechanism to the Kia EV6 fault, reflecting the shared E-GMP VCU architecture. Unpatched vehicles remain at risk of stranding without warning.

  What you would notice

  • Vehicle will not enter Ready mode after normal start procedure
  • Instrument cluster powers on but Ready indicator absent and drivetrain silent
  • Multiple simultaneous DTE, EV system, and check vehicle warnings
  • Fault may resolve temporarily after hard reset via 12V disconnect
  • Recurrence rate increases without VCU firmware patch

  Typically $0–$4,800 to put right.

• Costly issue

  Test heat pump operation on a cold day.

  See why

  Heat pump refrigerant line fitting corrosion causing heating system failure

  The Ioniq 5 NE shares the e-GMP platform heat pump system with the Kia EV6, and the same galvanic corrosion issue affects the aluminium refrigerant line fittings where they connect to dissimilar metal components. Refrigerant leaks progressively degrade heat pump output, with complete failure in winter leaving only energy-intensive resistive heating. Hyundai issued a TSB addressing refrigerant line inspection and replacement in AU markets. The issue was documented within 2–4 years of service on NZ/AU examples.

  What you would notice

  • Insufficient cabin heating in cold weather
  • Heat pump error message or warning light
  • Battery range significantly reduced in winter (resistive heating compensating)
  • Refrigerant loss indicated by system warning

  Typically $900–$2,800 to put right.

• Costly issue

  Check battery label for manufacture date.

  See why

  12V Auxiliary Battery Failure Causing Not-Ready State

  The Ioniq 5 relies on a small 12V lead-acid auxiliary battery to power low-voltage systems including the body control module, door locks, exterior lighting, and the pre-charge relay required to initiate high-voltage system startup. Unlike a conventional vehicle it is recharged intermittently by a DC-DC converter rather than continuously by an alternator, resulting in charge cycling stress that degrades the battery faster than typical. When the 12V battery develops high internal resistance or a failed cell, the vehicle cannot complete the high-voltage pre-charge sequence and will not enter Ready mode. Door locks malfunction erratically and interior lights may flicker. Owners report the 12V battery can fail sooner than in a conventional car. Hyundai recall 41D033 (REC-005942, 2024) updates the charging control unit (ICCU) software on 2021 to 2024 cars.

  What you would notice

  • Vehicle fails to enter Ready mode with high-voltage battery shown as adequately charged
  • Door locks slow or unresponsive — key fob proximity range reduced
  • Flickering interior lighting or instrument cluster dimming during startup sequence
  • 12V battery warning displayed on instrument cluster or via Bluelink notification
  • Temporary recovery after 12V jump-start but fault recurs within days

  Typically $380–$950 to put right.

• Costly issue

  Request a Hyundai GDS2 battery capacity and cell-balance report from a dealer and examine individual module state-of-health percentages.

  See why

  77.4kWh BMS Cell Voltage Imbalance & Range Loss

  The 77.4kWh lithium-ion battery pack fitted to long-range Ioniq 5 variants develops progressive inter-module cell voltage imbalance in packs subjected to frequent 350kW DC fast charging or habitual partial-state-of-charge cycling without periodic full-balance charges. The BMS passive balancing system cannot correct large inter-module divergence once established. Affected vehicles exhibit measurable range degradation below the expected age-adjusted figure, with the usable state-of-charge window narrowing asymmetrically. Advanced cases see the BMS restrict charging to protect weaker cells and Hyundai's own capacity evaluation may flag the affected module for replacement under the battery warranty. Identical architecture to EV6 pack with same failure progression.

  What you would notice

  • Displayed range at 100 percent charge consistently 15 percent or more below age-adjusted expectation
  • Non-linear state-of-charge drop — rapid fall in final 20 percent of displayed charge
  • BMS reduced-charging-rate alert during 350kW DC fast charge sessions
  • Bluelink app showing degraded battery health trend over recent months
  • GDS2 module voltage spread exceeding 50mV at rest on individual cell group pairs

  Typically $5,500–$22,000 to put right.

• Costly issue

  Scan for inverter over-temperature DTCs and review freeze-frame ambient and coolant temperature data at fault occurrence.

  See why

  800V Inverter IGBT Thermal Stress Power Reduction

  The front and rear motor inverter IGBT modules in the 800V E-GMP drivetrain are susceptible to thermal cycling fatigue under sustained high-load conditions in ambient temperatures above 28C. The power control unit detects rising junction temperatures and progressively derate output, triggering a power reduction warning. In severe cases the vehicle enters limp mode with output capped below 30kW. NZ and AU summer driving, particularly towing or sustained motorway grades, accelerates IGBT solder joint degradation. Hyundai released thermal management calibration updates but hardware replacement is required in advanced cases. Shared platform architecture with EV6 means identical failure mode and repair approach.

  What you would notice

  • Amber or red power reduction warning on instrument cluster
  • Sudden acceleration cut to below 30 percent of normal output
  • Vehicle enters limp mode during sustained motorway or hill driving
  • Fault codes P0A09, P1A14, or inverter over-temperature DTC stored
  • Warning clears after 20-40 minutes of low-load cooling but recurs

  Typically $7,500–$18,000 to put right.

Hyundai Ioniq 5 service schedule

What falls due, and at what distance, for each generation of the Hyundai Ioniq 5. These are the model’s intervals — the car’s own service book is the only thing that can tell you what has actually been done to it.

What these repairs cost on other cars

Some of the Hyundai Ioniq 5’s documented faults are repairs other models share. Each page lists the documented NZ cost for every model it affects.

• EV Battery Replacement Cost

Other Hyundai models