Investigations
Unexpected ADS behavior
NHTSA Preliminary Evaluation PE24016 — closed, opened 2024-05-13.
NHTSA investigation PE24016 is a Preliminary Evaluation opened on 2024-05-13 and currently closed. The subject is tracked inside the Office of Defects Investigation queue. Latest activity on this investigation was logged on 2025-07-22 — NHTSA updates that field whenever an Information Request goes out, a supplement is filed, or a status change is recorded in the public docket.
A Preliminary Evaluation like PE24016 is the entry point of the federal defect-investigation process. NHTSA engineers scan complaint databases, field reports, and manufacturer data to decide whether an Engineering Analysis is warranted, whether a voluntary recall is already sufficient, or whether the pattern does not rise to a defect finding.
Investigators summarized the matter as follows: "On May 13, 2024, the Office of Defects Investigation (ODI) opened a Preliminary Evaluation (PE24016) to investigate the Waymo 5th Generation automated driving system’s (ADS) performance based on 22 reports of unexpected..." Investigations are the early-warning layer of the federal auto-safety system, sitting upstream of formal recalls and defect orders. Whether this one closes without action or escalates into an Engineering Analysis, the full history stays in the ODI archive so researchers, litigators, and buyers can pull the paper trail at any time.
Investigation Summary
On May 13, 2024, the Office of Defects Investigation (ODI) opened a Preliminary Evaluation (PE24016) to investigate the Waymo 5th Generation automated driving system’s (ADS) performance based on 22 reports of unexpected driving behaviors identified through Standing General Order 2021-01 (SGO) and other publicly available sources. The initial reports and additional reports received during the investigation included incidents in which a Waymo ADS-equipped vehicle was the sole vehicle operated during a collision or in which the ADS-equipped vehicle exhibited driving behavior that potentially violated traffic safety laws. ODI identified 367 total incidents during the investigation with 109 crashes, of which 102 met SGO reporting criteria and were reported by Waymo under the SGO. Incidents involving potential traffic safety law violations included both non-crash and crash incidents and involved behaviors such as unexpected responses to traffic control devices and entering construction zones. One crash incident involved an injury. Crashes and non-crash incidents that involved traffic safety law concerns had no injuries reported. Within the set of identified incidents, ODI focused its review on a pattern of crashes where Waymo vehicles struck stationary or semi-stationary objects such as gates, barriers, chains, and other objects with similar physical characteristics. Waymo conducted two recalls during the investigation to improve perception and response to objects. Recall 24E049 was filed on June 10, 2024, regarding software updates made following a May 2024 crash in which an unoccupied Waymo vehicle struck a utility pole. Waymo also updated the ADS system to improve the detection and avoidance of roadway barriers, such as chains strung across the path of travel, gates, and other gate-like roadway barriers and filed Recall 25E034 on May 12, 2025. In view of the recall actions taken by Waymo and ODI’s analysis of the available data, ODI is closing this Preliminary Evaluati
About This Investigation Type
A Preliminary Evaluation (PE) is the first phase of NHTSA's investigation process. It is opened when the agency identifies a potential safety defect pattern, usually triggered by consumer complaints, manufacturer reports, or field monitoring. During a PE, NHTSA gathers information to determine whether a formal engineering analysis is warranted.
Data from NHTSA Office of Defects Investigation. Cross-references: NHTSA recall campaign API and NHTSA FARS where fatality records overlap. PlainCars does not rate or recommend vehicles. Learn more.
Read our methodology — how this data is sourced, computed, and verified.