NHTSA Office of Defects Investigation
Preliminary Evaluation PE23-010: Automatic Emergency Braking Errors
- Closed
NHTSA's Office of Defects Investigation opened Preliminary Evaluation PE23-010 on May 26, 2023 and closed it on October 23, 2025, the day it opened Engineering Analysis EA25-006, whose summary cites it. NHTSA's investigations file lists the Freightliner Cascadia and Western Star 5700 for it.
Updated daily from NHTSA's investigations file
Key facts
- NHTSA number
- PE23-010 (also written PE23010)
- Investigation type
- Preliminary Evaluation The first stage of most defect investigations: NHTSA's Office of Defects Investigation gathers basic information about a possible safety defect, including from the manufacturer.
- Status
- Closed October 23, 2025
- Opened
- Closed
- Vehicle or equipment manufacturer
- Daimler Trucks North America, LLC
- Component
- Forward Collision Avoidance — Dynamic Brake Support/Brake Assist
- Vehicles and equipment
- Freightliner Cascadia and Western Star 5700
A recall appears here only when NHTSA's investigations file links one to the investigation; NHTSA's summary or record can name others.
NHTSA's summary
As NHTSA's Office of Defects Investigation wrote it for Preliminary Evaluation PE23-010.
try.vin does not copy NHTSA's investigation documents; NHTSA's investigation record lists the ones NHTSA has published.
On May 26, 2023, the Office of Defects Investigation (ODI) opened a Preliminary Evaluation (PE23010) to assess reports of false positive activation of the Automatic Emergency Braking (AEB) system in model year (MY) 2017-2022 Daimler Trucks North America (DTNA) vehicles. The reports alleged that activation of the AEB system occurred while driving with no apparent obstruction in the vehicle's forward path, resulting in unexpected and sudden vehicle deceleration. ODI sent an information request letter to DTNA on June 15, 2023.
In its September 1, 2023, response, DTNA indicated that it received of a total of 315 reports that may relate to the alleged defect in MY 2017-2022 DTNA vehicles. DTNA stated that the vast majority of false positive activation of the subject systems occur for very limited durations and result in a five mile per hour deceleration. ODI considered four AEB systems offered by DTNA: Detroit Assurance 2.0, Detroit Assurance 4.0, Detroit Assurance 5.0, and Wabco OnGuard. ODI’s analysis shows that of the Detroit Assurance versions, all fail at similar rates. The Wabco OnGuard AEB systems equipped on the same model and model year vehicles have experienced a significantly lower claim rate. To date, ODI has received a total of 32 consumer complaints of inadvertent activation of AEB in MY 2017-2022 DTNA vehicles. In total, ODI reviewed 347 unique (i.e., non-duplicative Vehicle Identification Number) reports that may relate to the alleged defect, which include 24 involving a crash, 13 reports involving an alleged injury and one report with a fatality. PE23010 has been upgraded to an Engineering Analysis (EA25006) to further assess the scope, frequency, and nature of the inadvertent AEB activations in MY 2017-2022 Freightliner Cascadia and Western Star 5700 vehicles.
In particular, this EA will assess the safety consequences likely to arise in the scenarios during which the AEB inadvertently and unexpectedly activates, such as the speeds and conditions during which the activation occurs. To review the ODI reports cited in the Closing Resume ODI Report Identification Number document, go to NHTSA.gov.
Vehicles and equipment listed for this investigation
NHTSA's investigations file lists these vehicles and equipment for Preliminary Evaluation PE23-010. A listed model year means only that an investigation names it; it says nothing about any particular vehicle. Model years with a try.vin recall page link to that page's NHTSA investigations section.
What an NHTSA investigation is
NHTSA's Office of Defects Investigation (ODI) looks into possible safety defects in vehicles and equipment, often after owner complaints. An investigation usually starts as a Preliminary Evaluation, or as a Recall Query when it concerns whether an existing recall covers the right vehicles or fixes the problem, and ODI can upgrade it to a more detailed Engineering Analysis. A Defect Petition asks NHTSA to open an investigation, and Audit and Equipment Queries are administrative investigations into whether companies complied with federal vehicle safety requirements, such as reporting, recall and certification rules.
An open investigation is not a finding that a safety defect exists, and NHTSA can close one without a recall.
To see whether a specific vehicle has an open recall, enter its VIN at nhtsa.gov/recalls.
Free VIN check: decode a VIN to see its year, make and model.
Sources
NHTSA's investigation record for PE23-010
Investigation details come from NHTSA's investigations file, which try.vin imports once a day. The investigation types are described from the U.S. Department of Transportation Inspector General's May 2023 report on NHTSA's Office of Defects Investigation, NHTSA's petition rules (49 CFR Parts 552 and 557) and NHTSA's Office of Defects Investigation procedures. How try.vin reads NHTSA investigations.