Hyundai Ioniq 9 Long Range AWD Mk1

The ICCU is the most significant known weakness of the E-GMP platform. It manages energy flow between the high-voltage battery, the 12V system, and external chargers. When it fails, the 12V battery drains gradually (even while driving), leading to loss of drive power, inability to charge, or complete immobilization. Root causes include overvoltage transients during charging and thermal stress. Between 2 and 10 percent of E-GMP owners have experienced ICCU-related issues depending on model year. Hyundai extended ICCU warranty coverage to 15 years / 300,000 km in Germany for Ioniq 5 and 6 models built before mid-2024. The Ioniq 9 uses an updated ICCU design with improved cooling, but early reports of ICCU-related symptoms (speed limiting, high-pitch charging noise, constant battery conditioning) have appeared on owner forums. Under warranty, the repair is free. Out-of-warranty ICCU replacement costs approximately €1,500-2,500 for the unit plus €500-1,000 labor, with reported wait times of 1-2 months for replacement units.

E-GMP vehicles have a relatively high parasitic drain on the 12V battery. If the car sits parked for 5-14 days without driving or plugging in, the 12V battery can deplete to the point where the car will not start or shift out of park. The ICCU is supposed to periodically top up the 12V battery from the main pack, but software glitches or suboptimal ICCU management can prevent this. Hyundai identified the BlueLink telematics system as a major contributor, with some vehicles receiving up to 5,000 server requests per day, and issued a software update limiting traffic to 20 per day. The fix is straightforward: keep the car plugged in when parked for extended periods. Replacement of the 12V battery costs approximately €200-300, plus potential towing if the car is stranded. Multiple owners report needing 12V battery replacement within the first 2 years due to deep discharge damage.

The AWD variant uses a mechanical clutch disconnector on the front motor to reduce drag when only the rear motor is driving. This disconnector produces a noticeable revving or low hum when the front motor is not engaged, particularly in Eco and Normal drive modes. Sport mode is typically silent because the front motor stays engaged. On Ioniq 5 AWD models (same E-GMP platform), German forums report roughly 50% of AWD vehicles are affected, with the noise becoming more pronounced at temperatures above 20 degrees Celsius. The only dealer remedy is replacement of the entire front motor/clutch assembly. Under warranty this is free; out of warranty the front drive unit replacement costs approximately €2,000-3,000 including labor. Parts availability has been limited in some regions. The noise is cosmetic rather than mechanically dangerous, but many owners find it unacceptable in a premium vehicle.

E-GMP vehicles with heat pumps (standard on AWD models) are susceptible to PTC heater and heat pump component failures. Symptoms include lukewarm or completely cold air from the vents despite the heat being set to maximum. Hyundai issued TSB 23-HA-002H addressing this on Ioniq 5 and 6 models. The PTC heater replacement requires extensive dashboard removal (8-10 hours labor), making it expensive even when the part itself is relatively affordable. One UK dealer quoted approximately €4,500 total (part + labor). Some owners report persistent heating issues lasting months with multiple repair attempts. The Ioniq 9 uses an updated HVAC system, but the underlying architecture is shared with earlier E-GMP models. Under the 5-year warranty, this repair is covered. For used buyers outside warranty, independent specialists may offer lower labor rates.

One Ioniq 9 owner reported complete infotainment failure after 1.5 days of ownership, with the car in the shop for 5 weeks awaiting parts. Across the E-GMP platform, screen blackouts, touchscreen unresponsiveness, and failed software updates are recurring complaints. A soft reset (holding the power button for 10 seconds) often restores function temporarily. If the head unit hardware fails, dealer replacement costs €2,500-3,500. Software updates via OTA have improved stability on later production units, but the issue persists. Under warranty, repairs are covered. For used buyers outside the 5-year warranty, this can be an expensive repair.

The Ioniq 9's driver attention warning system uses an infrared camera to track the driver's eyes. Many owners report false inattention warnings, particularly when wearing glasses or sunglasses. The IR sensor loses tracking when sunlight creates glare on lens surfaces. In extreme cases, the system has triggered emergency braking or deactivated Highway Driving Assist mid-drive. Hyundai issued TSB 25-GI-001H acknowledging problems with glasses, seating position, and sun glare. The system can be disabled in settings, though doing so removes a safety feature. No repair cost unless the sensor itself fails, in which case recalibration or replacement runs €150-300.

Hyundai recalled certain 2025-2026 Ioniq 5 and 2026 Ioniq 9 vehicles because the battery system may contain an improperly tightened bus bar, caused by rework errors at the battery supplier. The issue affects a small number of vehicles (27 units in the initial US recall). Dealers inspect and tighten the bus bar retention bolts or replace the battery assembly free of charge. This is a manufacturing quality control issue affecting a very small production batch, not a design flaw.

Hyundai recalled certain 2025-2026 Ioniq 5 and Ioniq 9 vehicles produced between December 2024 and July 2025 for potentially under-torqued rear suspension fasteners. Symptoms include abnormal noise and vibration from the rear axle. If bolts detach while driving, vehicle control could be compromised. The recall covers US-produced vehicles from the Georgia Metaplant. European-delivered cars (built in South Korea) may have different production processes. Dealers inspect and re-torque or replace rear suspension fasteners free of charge. Only 172 Ioniq 9 units were initially affected.