- Safety recall
- A safety recall is issued when a manufacturer or NHTSA determines that a vehicle has a safety-related defect or does not comply with a federal motor vehicle safety standard. Recall repairs are free. Whether a specific vehicle is covered depends on its VIN — a recall listed for a model year does not necessarily apply to every vehicle of that year.
- Safety investigation
- NHTSA opens an investigation to examine whether a safety defect may exist. An open investigation is not a determination that a defect exists, and many investigations close without a recall. Investigations can, however, lead to one.
- Manufacturer communication
- Manufacturers file copies of the bulletins they send to dealers with NHTSA. These often describe diagnostic or repair procedures for a known condition. They are not recalls: repairs described in a bulletin are usually only free if the vehicle is still under warranty or the manufacturer has extended coverage.