2025 Hyundai Ioniq 5 HV Battery Charging Issue TSB

Hyundai has released Technical Service Bulletin (TSB) 26-EV-002H, superseding previous bulletin 25-EV-002H, to address a specific charging concern affecting certain 2025 Hyundai Ioniq 5 (NEA EV) vehicles. This bulletin provides updated information regarding production dates, part numbers, operation codes, and the approval process for Battery System Assembly (BSA) replacement.

The TSB focuses on conditions where a voltage difference between battery cells prevents the High Voltage Battery from achieving a full charge. If you own a 2025 Hyundai Ioniq 5 and are experiencing issues with the HV battery not fully charging, this information is highly relevant.

Symptoms

Owners of affected 2025 Hyundai Ioniq 5 vehicles may notice that their High Voltage Battery does not fully charge. This condition is caused by a voltage imbalance between individual battery cells within the High Voltage Battery system. The primary symptom is the inability to reach a 100% state of charge, even after prolonged charging.

Fault Codes / DTCs

This charging issue is specifically linked to two Diagnostic Trouble Codes (DTCs):

• P1AA700: Hybrid/EV Battery Abnormal Performance: Cell Voltage Deviation
• P1AD300: Hybrid/EV Battery Abnormal Performance: MISD

If either of these DTCs are found in an "Active" status, it indicates the presence of the condition described in TSB 26-EV-002H, leading to the necessary inspection and potential replacement of the Battery System Assembly (BSA).

Diagnosis

To diagnose the 2025 Hyundai Ioniq 5 HV battery charging issue, technicians will use the Global Diagnostic System (GDS) to perform a fault code search on the Battery Management System (BMS). The presence of active DTCs P1AA700 and/or P1AD300 confirms the condition. If these codes are active, a Prior Approval (PA) submission is required for the replacement of the Battery System Assembly (BSA). If these DTCs are not active, technicians will proceed with normal diagnostic procedures.

Important Warnings for Owners

Owners should be aware of several critical points outlined in TSB 26-EV-002H:

• Justification Required: This field action requires a confirmed customer concern and a verified symptom related to the TSB before any repair work can begin. Claims submitted without proper justification may be subject to debit.
• Certified Dealers Only: To prevent potential damage to IONIQ vehicles, all repairs must be performed exclusively at IONIQ certified dealers.
• Warranty Claims: If a part needs replacement under this TSB and is still under warranty, a separate claim should be submitted. For parts out of warranty, a Prior Approval request for goodwill consideration is necessary before performing the work.
• High Voltage System Safety: Technicians are reminded to strictly follow the "Safety Precautions, Cautions and Warnings" and "High Voltage Cut-off Procedure" sections of the shop manual when working on the high voltage system. Failure to comply can result in serious accidents due to electric shock or leakage.

Repair Procedure Summary

The repair for the 2025 Hyundai Ioniq 5 HV battery charging issue, as detailed in TSB 26-EV-002H, involves the following steps:

1. DTC Verification: A technician will use the GDS tool to check for active DTCs P1AA700 or P1AD300 in the Battery Management System (BMS).
2. Prior Approval: If either DTC is active, a Prior Approval (PA) request must be submitted to Hyundai for the Battery System Assembly (BSA) replacement.
3. Digital Documentation: Before replacement, a photo of the new BSA's part label must be taken using the STUI camera function and uploaded. If STUI camera is unavailable, the last 6 digits of the VIN and the repair date must be written on paper and included in the photo.
4. BSA Replacement: The Battery System Assembly (BSA) will be replaced according to the detailed procedures outlined in the shop manual under "Battery Control System > High Voltage Battery System > Battery System Assembly (BSA) > Removal / Installation."
5. Fastener Torque: Technicians must ensure all fasteners are torqued to the recommended specifications to prevent future issues.

Required Tools or Parts

The repair procedure outlined in TSB 26-EV-002H requires specific parts for the replacement of the Battery System Assembly (BSA):

• Battery System Assy (Long Range): Part Numbers 37501-P1020, 37501-P1050, 37501-PI900, 37501-P1920 (Qty: 1)
• Battery System Assy (Short Range): Part Numbers 37501-P1120, 37501-P1150, 37501-P1820 (Qty: 1)
• Bolt & Washer Assy (BSA): Part Number 37535-G1050 (Qty: 8)
• Bolt & Washer Assy (BSA): Part Number 37535-G1500 (Qty: 18)
• Pink-Antifreeze / Coolant: Part Number 00232-19098 (Qty: 2)

Owner Action

If you own a 2025 Hyundai Ioniq 5 and suspect your vehicle is experiencing the 2025 Hyundai Ioniq 5 HV battery charging issue, or if you have seen a check engine light related to battery performance, it is recommended to contact your nearest IONIQ certified Hyundai dealer. They can perform the necessary diagnostic checks, including scanning for DTCs P1AA700 and P1AD300, and determine if your vehicle qualifies for the repair under TSB 26-EV-002H. This repair is covered under High Voltage Coverage (EV/HEV/PHEV) warranty.

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Source: NHTSA ID: 11029938