Chevrolet Silverado 1500 2025 — technical service bulletin
Bulletin 662.21 · NHTSA communication 11036471 · issued Aug 5, 2026
Technical service bulletin
communication type
Unknown / Other
component
2025
model years
2
vehicle entries
Official summary
• Fixes to help ensure proper functionality for heating and cooling features. • Improvements to night mode lights for shifting gears. • Fixes for Daytime Running Lamps turning on when set to Off. • Fixes to help prevent erroneous missing key messages on driver display. • Fixes for accuracy of low tire pressure alert. • Fixes for speed threshold for pedestrian alerts. • Improvements to start reliability and reduced check engine light activation • Improvements to turbo system diagnostics • Improvements to reliability when extending the running boards on your vehicle • Improves transmission diagn
Vehicles covered
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.