Mazda CX-30 2019–2021 — technical service bulletin
Bulletin SA-003-22a · NHTSA communication 10208560 · issued Feb 4, 2022
Technical service bulletin
communication type
Electrical System
component
2019–2021
model years
5
vehicle entries
Official summary
Some vehicles may store DTC U0300:57 (Body control module (BCM) internal malfunction) after a BCM replacement or MDARS BCM software update (NOT with BCM update for SSPC5 or 4621B using MDRT) and the DTC cannot be erased. This is caused by a BCM-VCM software error. Mazda is aware of the issue and is working on a resolution. If there is an issue with this concern, contact Hotline for newest repair information. DO NOT perform BCM software update with MDARS until further notice, including CSP06 and CSP07. This SA will be updated with the newest repair information as it becomes available.
What a TSB means. Technical service bulletins are repair guidance manufacturers send to dealers — they are not recalls, and repairs are not automatically free (warranty extensions are an exception worth checking). The full document is available via NHTSA’s vehicle lookup.