Hyundai’s official materials document an IONIQ 5 Integrated Charging Control Unit (ICCU) fault that can stop the 12-volt battery from charging and may trigger warning lights or reduced-power operation. The remedy depends on a diagnostic check, and recall coverage applies only to certain vehicles. Check your VIN and have any recall work handled by an IONIQ-certified dealer.
What the IONIQ 5 ICCU does
The Integrated Charging Control Unit charges the vehicle’s 12-volt auxiliary battery and powers low-voltage accessories. If it fails to charge that battery, the vehicle can lose low-voltage electrical support. Hyundai’s Recall 257 bulletin describes this charging fault and identifies diagnostic trouble code P1A9096, “DC/DC Converter Input Voltage Sensor Fault.”
Symptoms described in Hyundai’s recall materials
Hyundai says an ICCU fault can lead to low 12-volt battery charging. The vehicle may display warning lights, sound an audible chime, show an instruction to stop, and enter reduced-power mode. Hyundai’s March 2024 Recall 24V-204 owner notification states: “The ICCU may become damaged and stop charging the 12-volt battery.”
If a stop or reduced-power warning appears, treat it as an urgent safety warning: follow the vehicle display and owner-manual instructions, and arrange qualified assistance. Do not attempt high-voltage repairs.
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Which IONIQ 5 vehicles are covered by Recall 272?
Hyundai Recall 272 covers certain 2022–2024 model year IONIQ 5 vehicles produced from October 4, 2021 through October 9, 2024. Those model years and production dates define the range in the recall document; they do not mean every vehicle in that range is included. A model year alone also cannot show whether an individual vehicle has an open recall or whether its remedy has already been completed.
Check the vehicle identification number (VIN) with Hyundai or NHTSA, then ask Hyundai whether the current remedy remains outstanding. Hyundai’s December 23, 2024 dealer notification says the recall “can only be performed at IONIQ certified dealers.”
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How the official ICCU recall remedy works
For Recall 272, the dealer checks for diagnostic trouble code P1A9096. Hyundai’s specified repair depends on that result:
| Diagnostic result | Recall 272 remedy |
|---|---|
| P1A9096 is not found | Perform the software update. |
| P1A9096 is found | Replace the ICCU and fuse, with a software update as needed. |
The bulletin lists ICCU part number 36400-1XAA0QQH for the repair when the specified code is found; it says the fuse is ordered with the ICCU. This is dealer repair information, not an owner-installation recommendation. Hyundai restricts the recall work to IONIQ-certified dealers.
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What to do if your 12-volt battery keeps dying
- Check for an urgent warning. If the vehicle displays a stop or reduced-power warning, follow the on-screen and owner-manual instructions and arrange qualified assistance.
- Check recall status by VIN. Contact Hyundai or use NHTSA’s recall lookup to determine whether the specific vehicle is affected and whether the remedy is still open.
- Ask an IONIQ-certified dealer about the ICCU diagnosis. Ask whether P1A9096 is stored and which Recall 272 procedure applies to the vehicle.
- Do not treat a 12-volt battery replacement alone as the recall repair. Hyundai’s procedure is based on diagnostic results and may require ICCU and fuse replacement, rather than only replacing the auxiliary battery.
How common is the ICCU problem?
Hyundai’s recall materials document the fault and define which vehicles may be covered, but they do not establish a fleetwide failure rate. The affected production range is a recall-eligibility boundary, not a measure of how often the fault occurs. These materials therefore support describing the ICCU fault as a documented recall issue, not quantifying it as common across all IONIQ 5 vehicles.
Independent reader supportYour contribution helps us test, update, and keep practical guides available for everyone.What this guide can and cannot confirm
The official materials reviewed here establish the ICCU and 12-volt charging concern, the P1A9096 diagnostic path, and the Recall 272 remedy. They do not establish prevalence or current official remedies for other alleged IONIQ 5 problems, so those should not be treated as confirmed common issues on this evidence alone.
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