P1AD3 · 原廠技術資料

HYUNDAI · 2026-10-12

Certain IONIQ 5 (NEA EV) vehicles may experience Malfunction Indicator Lamp (MIL) illumination and false battery overtemperature fault diagnosis caused by water ingress into the high voltage battery system. This condition may cause unnecessary fail-safe activation, potentially resulting in reduced vehicle performance or limited vehicle operation if the vehicle is continually driven. This bulletin provides the service procedure to update the Battery Management System (BMS) software to optimize the fail-safe activation logic to prevent false activation. Additionally, diagnostic criteria for DTC P1AD300 “Hybrid/EV Battery Abnormal Performance: MISD” has also been improved to enhance diagnostic accuracy.

HYUNDAI · 2025-04-12

Certain 2025MY IONIQ 5 (NEA EV) vehicles may experience a charging issue where a voltage difference between battery cells prevents the High Voltage Battery from fully charging. The two DTCs associated with this issue are: • P1AA700 – Hybrid/EV Battery Abnormal Performance: Cell Voltage Deviation • P1AD300 – Hybrid/EV Battery Abnormal Performance: MISD. If either of the DTCs listed above are identified in "Active" status, follow the procedure outlined in this TSB to replace the Battery System Assembly (BSA).