Chevrolet Blazer EV 2024–2026 — technical service bulletin
Bulletin 653.20 · NHTSA communication 11025933 · issued Nov 18, 2025
Technical service bulletin
communication type
Unknown OR Other
component
2024–2026
model years
3
vehicle entries
Official summary
This software update includes the following, if your vehicle is equipped: • Improvements to battery health diagnostics. • Fixes for efficiency when using fast charging stations. • Improvements to reliability for climate control and charging. • Improvements to the accuracy of efficiency values. • Improvements to shifting. • Fixes to protect battery health and adjust charge limits. During the update process, your radio may stay on up to 5 minutes after you exit the vehicle. This is expected behavior when an update package is onboard the vehicle. Do not service your vehicle during installation.
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.