Freightliner and Western Star preliminary evaluation PE23010
Automatic Emergency Braking Errors. NHTSA’s Office of Defects Investigation opened this preliminary evaluation about the dynamic brake support/brake assist on 12 model years (2017–2022). Opened May 26, 2023, closed Oct 23, 2025 after 2.4 years without a recall. closed
What NHTSA says
Source: Office of Defects Investigation, as filedOn 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.
A Preliminary Evaluation is the first formal stage: NHTSA has decided the complaints and other information it screened are worth a closer look, and asks the manufacturer for its own data on the condition. The summary is the agency’s own text from its investigation file, unedited; the resumes carrying the full reasoning are linked below.
The paperwork NHTSA filed
Source: every document on this action, at nhtsa.gov- Opening resume — ODI’s own summary of why it opened this — the subject, what prompted it, and the vehicles in scope.
- Closing resume — ODI’s own summary of why it closed this, and what it concluded.
| Document | Code | Filed | At NHTSA |
|---|---|---|---|
| Opening resume | INOA | 2023 | |
| Closing resume | INCLA | 2023 | |
| Information request to the manufacturer | INIM | 2023 | |
| Manufacturer's response — full submission | INRL | 2023 | |
| Memo granting a response extension | INRE | 2023 | 2 files 12 |
| Correspondence | INLO | 2023 | |
| Filed document | INCV | 2023 |
These are NHTSA’s own files, served from the agency’s site — the resumes are what ODI wrote when it opened and closed the action, and the rest is the correspondence behind them, including what the manufacturer sent when the agency asked. They are linked, not copied: where a document names the people who wrote in, that redaction is the agency’s to make and its copy is the one you should read.
What owners had already reported
Source: complaints on file the day it openedWhen NHTSA opened this on May 26, 2023, owners had filed 119 complaints with the agency about the model years above, of which 25 named the forward collision avoidance NHTSA went on to investigate. Owner complaints are the agency’s main early signal: ODI screens them, and a Preliminary Evaluation is usually where a pattern in them ends up.
This is what the complaint file held on that date, not a claim about which reports prompted the investigation — NHTSA’s complaint records carry no investigation number, so nobody can make that link from the data alone. The opening resume linked above names the reports ODI itself cited. Complaint records on this site begin with 2016.
What this means for an owner
Source: and what happens nextAn investigation is not a finding that a defect exists, and it puts no duty on anyone. NHTSA opens a Preliminary Evaluation when complaints and other reports suggest a condition worth asking the manufacturer about; it upgrades to an Engineering Analysis when the answers warrant testing; it closes either when it recommends a recall, when the manufacturer recalls on its own, or when no defect trend is found. The agency’s own goals are about four months for a petition, eight for a Preliminary Evaluation or a Recall Query and eighteen for an Engineering Analysis; many run longer.
This one closed without a recall. That means NHTSA found no defect trend it chose to act on at the time, or the manufacturer addressed the condition another way (a service campaign or a bulletin, which have their own pages). A closed file can be reopened if new reports arrive.
Model years it names
Source: as NHTSA filed themAlso named: 2017 Freightliner Cascadia; 2018 Freightliner Cascadia; 2019 Freightliner Cascadia; 2020 Freightliner Cascadia; 2021 Freightliner Cascadia; 2022 Freightliner Cascadia; 2017 Western Star 5700; 2018 Western Star 5700; 2019 Western Star 5700; 2020 Western Star 5700; 2021 Western Star 5700; 2022 Western Star 5700.
A vehicle page’s investigation list carries the same action; a name here is the scope NHTSA opened, not a list of affected VINs.
Common questions
Source: NHTSA Office of Defects InvestigationIs PE23010 a recall?
No. A preliminary evaluation is NHTSA asking questions, not a recall. A safety recall carries an NHTSA campaign number and a duty to repair for free; this one closed without one. Whether one particular vehicle has an open recall is a VIN question at nhtsa.gov/recalls.
Is PE23010 still open?
No. It closed on Oct 23, 2025 without a recall.
Which vehicles does PE23010 cover?
NHTSA opened it on 12 model years: 2017 Freightliner Cascadia, 2018 Freightliner Cascadia, 2019 Freightliner Cascadia, 2020 Freightliner Cascadia, 2021 Freightliner Cascadia, 2022 Freightliner Cascadia and more. That is the scope of the inquiry, not a list of affected vehicles; a recall, if one follows, defines its own population by VIN.