Brightdrop Zevo 400 2024–2026 — technical service bulletin
Bulletin PIT6411B · NHTSA communication 11023903 · issued Oct 1, 2025
Technical service bulletin
communication type
Unknown / Other
component
2024–2026
model years
33
vehicle entries
Official summary
This information provides software update information for the K73 Telematics module to correct the symptoms described.
Vehicles covered
- 2024 Brightdrop Zevo 400
- 2025 Buick Envision
- 2026 Buick Envision
- 2025 Cadillac CT5
- 2026 Cadillac CT5
- 2025 Cadillac Lyriq
- 2026 Cadillac Lyriq
- 2025 Cadillac Optiq
- 2026 Cadillac Optiq
- 2025 Cadillac XT4
- 2026 Cadillac XT4
- 2025 Chevrolet Blazer
- 2026 Chevrolet Blazer EV
- 2025 Chevrolet Brightdrop 400
- 2026 Chevrolet Brightdrop 400
- 2026 Chevrolet Brightdrop 600
- 2025 Chevrolet Colorado
- 2026 Chevrolet Colorado
- 2025 Chevrolet Equinox
- 2026 Chevrolet Equinox
- 2025 Chevrolet Equinox EV
- 2026 Chevrolet Equinox EV
- 2025 Chevrolet Silverado EV
- 2026 Chevrolet Silverado EV
- 2025 Chevrolet Traverse
- 2026 Chevrolet Traverse
- 2026 GMC Acadia
- 2025 GMC Canyon
- 2026 GMC Canyon
- 2025 GMC Sierra EV
- 2026 GMC Sierra EV
- 2025 GMC Terrain
- 2026 GMC Terrain
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.