{"nhtsa_id":11023408,"type":"service_campaign","type_name":"Service campaign","date_added":"2025-10-01","date":"2025-09-23","document_id":"25-01-063H TSB","mfr_campaign":"T9E","replaces":null,"component":"ENGINE","mfr_system":null,"summary":"Certain IONIQ Electric (AE EV) and Kona Electric (OS EV) vehicles may exhibit a restricted coolant flow condition, which may be accompanied by a warning message (e.g., Coolant Supplement, Refill Inverter Coolant) in the cluster. No related DTCs are stored, and coolant level is normal in the reservoir tank. The coolant flow may be restricted by debris, causing abnormally high Electric Water Pump (EWP) speed. This TSB contains instructions for confirming high RPMs in the EWP, then using the Coolant Flushing Equipment Set to flush and clean debris from the various cooling system circuits. The coolant will be replaced with the updated Electric Vehicle Battery System Coolant (BSC-2) low-conductivity blue coolant.","document":{"url":"https://static.nhtsa.gov/odi/tsbs/2025/MC-11023408-0001.pdf","alternate_url":"https://static.nhtsa.gov/odi/tsbs/2025/MC-11023408-9999.pdf","confirmed":false},"url":"https://open.wenmarpro.com/bulletins/11023408","components":[{"id":"engine","name":"Engine","parent":null}],"codes":[],"topics":[],"vehicles":[{"make":"HYUNDAI","model":"IONIQ ELECTRIC","year_from":2020,"year_to":2021,"match":"base","vehicle_ids":["2020_hyundai_ioniq","2021_hyundai_ioniq"]},{"make":"HYUNDAI","model":"KONA ELECTRIC","year_from":2019,"year_to":2022,"match":"base","vehicle_ids":["2019_hyundai_kona","2020_hyundai_kona","2021_hyundai_kona","2022_hyundai_kona"]}],"as_of":"2026-10-19","note":"A bulletin is a manufacturer's communication to its dealers, as NHTSA indexes it. The summary is NHTSA's. The document is the manufacturer's: read it at NHTSA. A bulletin is not a recall, and listing a model year does not mean every vehicle of it is concerned.","attribution":[]}