PlainCars

Original research

Vehicle Components Most Linked to Crashes, Fires, and Fatalities

NHTSA component analysis ranking vehicle subsystems by how often a consumer complaint also records a crash, fire, injury, or death. Every figure on the page reflects the current NHTSA dataset as of your visit.

Published:

Compiled by PlainCars on 2026-06-04

Why some complaints become crashes

NHTSA Office of Defects Investigation records are voluntary complaint reports. Some include a crash or fire flag, but the flag is not an adjudicated finding that a component caused the incident. Rather than present raw complaint volume as a defect ranking, this analysis shows which component labels appear most often in reports that also carry those flags.

Raw complaint volume is influenced by fleet size, age, reporting behavior, and categorization. Across the 15 component systems shown here, reports carry 94,167 crash flags and 30,075 fire flags; a report can carry more than one flag. The figures describe submitted reports, not a component failure, injury, or vehicle-risk rate.

Which car parts cause the most crashes?

By absolute crash-flag count, the component label at the top of this dataset is AIR BAGS, appearing in 23,393 reports that also carry a crash flag. That is a description of the reports, not evidence that the component caused each crash or that it is riskier than another component.

The chart below renders the crash-flag count for each component label directly from the query result. Bars are sorted high to low by that report-field count.

Vehicle components most often linked to a crash

NHTSA complaint records that also report a crash, by component system, current as of your visit

crash-linked complaints

What this shows Air bags top the list because complaints reach NHTSA both when a bag deploys without cause and when one fails in a real collision; below them sit the systems a driver depends on to stay in control.

Source U.S. National Highway Traffic Safety Administration As of 2026

The components that escalate most

Absolute counts reward the component labels that appear in more reports. The table also shows a crash-flag share: crash-flagged reports divided by reports carrying that component label. It is shown only for labels with at least 500 reports, but it remains a share of submitted reports, not a component failure, injury, or vehicle-risk rate.

The largest visible crash-flag share is AIR BAGS:FRONTAL: 14,871 of 20,105 reports, or 74.0%. The visible-table median is 7.8%. That comparison is descriptive only: different components can be reported and categorized differently, and the database does not establish causation.

# Component system Complaints Crashes Fires Injuries Deaths Crash-flag share
1 AIR BAGS 126,744 23,393 764 24,921 700 18.5%
2 AIR BAGS:FRONTAL 20,105 14,871 243 13,039 233 74.0%
3 ELECTRICAL SYSTEM 180,040 3,993 9,814 3,556 186 2.2%
4 VEHICLE SPEED CONTROL 70,970 12,223 1,224 6,374 404 17.2%
5 ENGINE 157,570 2,863 6,707 2,489 136 1.8%
6 SERVICE BRAKES 73,857 7,997 723 4,187 111 10.8%
7 STEERING 113,465 5,849 653 3,860 285 5.2%
8 UNKNOWN OR OTHER 107,173 3,965 2,498 3,927 289 3.7%
9 SERVICE BRAKES, HYDRAULIC:ANTILOCK/TRACTION CONTROL/ELECTRONIC LIMITED SLIP 32,893 5,492 174 2,641 77 16.7%
10 STRUCTURE:BODY 46,325 3,634 1,036 3,351 110 7.8%
11 POWER TRAIN 127,919 3,754 858 2,053 59 2.9%
12 SEAT BELTS 20,351 2,801 159 3,807 168 13.8%
13 SERVICE BRAKES, HYDRAULIC 27,102 2,473 452 1,260 37 9.1%
14 ENGINE AND ENGINE COOLING:ENGINE:GASOLINE 18,005 271 2,588 334 59 1.5%
15 ENGINE AND ENGINE COOLING 39,068 588 2,182 510 47 1.5%

Source: U.S. National Highway Traffic Safety Administration, NHTSA Consumer Complaints Dataset. Crash, fire, injury, and death flags are counted from complaint records in the PlainCars component_summary table, queried live at request time.

Fire risk versus crash risk

Crash and fire flags are different report fields, and they do not track the same component labels. They may reflect different reporting and categorization patterns as well as different reported circumstances. Ranking the same labels by fire-flag count instead of crash-flag count reorders the list.

By fire-flag count the leader is ELECTRICAL SYSTEM, with 9,814 reports that also carry a fire flag. The second chart makes the difference in those two report-field distributions visible; it does not establish a cause for either outcome.

Vehicle components most often linked to a fire

NHTSA complaint records that also report a fire, by component system, a different failure mode from crashes

fire-linked complaints

What this shows Fire flags concentrate on the systems that manage current and heat, electrical and engine, which sit far lower on the crash ranking, showing the two hazards rarely share a root cause.

Source U.S. National Highway Traffic Safety Administration As of 2026

Where injuries and fatalities concentrate

The death column is a count of reports carrying a death flag. Among the labels shown here, AIR BAGS has the highest count at 700. Across the visible set, 2,901 reports carry such a flag. The data does not establish which component caused a death or a component-specific fatality rate.

How to read these numbers

A few cautions keep these figures honest. First, the crash, fire, injury, and death flags are self-reported fields on a complaint, not adjudicated findings. An owner who marks "crash" is telling NHTSA that a collision occurred in connection with the complaint; the agency does not confirm causation, and a single incident may be reported by several parties. Second, the counts are absolute, not normalized by how many vehicles carry each subsystem or how many miles they travel. Third, the same physical defect can be filed under several component labels depending on how the owner or the intake clerk categorized it. Read the table as a map of reported flags, not as a precise hazard rate for any component or vehicle.

If you are researching a specific vehicle, use the component links to understand the report record, then check its official recall status and the recall notice. Do not use a raw complaint count or report-flag share as a purchase, safety, or defect verdict.

Methodology and data notes

The figures on this page cover component labels with at least 500 reports, so a handful of records cannot create an unstable crash-flag share. The table’s crash-flag share is computed from the two displayed counts; it is a report-context measure, not a safety or defect rate.

The numbers on this page reflect the current NHTSA dataset as of your visit and update automatically as new data is published; nothing is hardcoded. The component links carry through to per-subsystem detail pages, and the methodology page documents the source file vintage and refresh cadence.

Related data

Sources