My Hyundai Ioniq 5 N lost power and won't charge. Is it the ICCU?

Short answer: Owners of the Ioniq 5 N have had the ICCU, the part that runs AC charging and keeps the 12V charged, fail with warnings and loss of power. It's a warranty repair at the dealer, though parts can take weeks. If you see warnings while driving, pull off safely. Ask the dealer about the 12V battery too.

Symptom: A warning appears, power drops or the car shuts down, and it won't charge on AC. Sometimes it starts with charging problems.

What to check first

1. If warnings appear while driving, pull off safely.
2. Note whether AC charging still works.
3. Have it towed to the dealer and ask for ICCU diagnosis.
4. Ask for a loaner, since parts can take weeks.
5. Ask whether the 12V battery was tested or replaced.
6. Run your VIN at nhtsa.gov/recalls.

Likely causes

1. Failed ICCU. The ICCU, or Integrated Charging Control Unit, handles AC charging and keeps the 12V battery charged from the main battery. When it fails, the car can show warnings, lose power and refuse to charge.
2. 12V battery problems linked to the ICCU. Some owners think the ICCU failures and 12V problems are connected, and a few replaced the 12V battery with a different type. That's owner experience, not a confirmed fix.

What it usually costs

Owners report ICCU replacements under warranty. Some waited weeks for parts.

Is it safe to keep driving?

No, not once it's failing. The car can lose power. Pull over safely and call roadside assistance.

DIY or shop?

Carrying a jump pack is your only DIY. An EV's high-voltage system can stay live with the car off. Leave the orange cables, the big battery and the charging hardware to a trained EV technician.

Recalls, bulletins and complaints in plain words

• Recalls: NHTSA's recall lookup for the 2025-2026 Ioniq 5, which includes the N, shows 10 recalls. None is an ICCU recall. 25V482000 and 26V068000 cover high-voltage battery bus bars that may be loose and short-circuit, and 25V065000 and 25V235000 cover the N's left-foot braking feature. Check your VIN at nhtsa.gov/recalls. If your car is part of a recall, the dealer fixes it for free.
• Plain words: The complaint count below shows how often owners reported problems that mention these words to NHTSA. A count is not proof of a defect.
• NHTSA complaints: 12 keyword-matched complaints for Hyundai Ioniq 5 N 2025–2026 (of 18 unique complaints queried, NHTSA complaints API by model year, queried 2026-11-01; keywords: iccu, charg, 12v, 12 volt, loss of power, power, battery, warning). This counts complaints that mention these words. It is not a defect finding.

What owners report

• In ICCU failure after 1 year and 9000 miles (UK) on Reddit r/Ioniq5N, a UK owner's Ioniq 5 N had an ICCU failure after one year and 9,000 miles during a heat wave. Other owners reported failures at 10 months and 3,500 miles with a long wait for parts, one with three ICCU failures in 16,000 miles, and another whose main battery failed instead and was in the shop for six weeks.
• In ICCU failure after almost 2 years and 6,200 km (Estonia) on Reddit r/Ioniq5N, an owner in Estonia had an ICCU failure after almost two years and 6,200 km. Others said there was no way to prevent it and asked whether the dealer covers it. The owner hoped the replacement would last longer.

Quick tip

Ask early for a loaner. Owners' biggest complaint wasn't the repair, it was waiting for parts.

Vehicle focus: Hyundai Ioniq 5 N, 2025-2026.

Safety / mechanic note

Sudden power loss on a highway is dangerous. Verify with a mechanic.