Chevrolet Cobalt 2004–2006 — technical service bulletin
Bulletin 3393A · NHTSA communication 10017006 · issued Oct 20, 2005
Technical service bulletin
communication type
Exterior Lighting
component
2004–2006
model years
11
vehicle entries
Official summary
Backlighting is inop during daylight conditions (headlight switch turned on manually) *sc
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.