NHTSA Office of Defects Investigation
Preliminary Evaluation PE25-015: Loss of braking force
- Closed
NHTSA's Office of Defects Investigation opened Preliminary Evaluation PE25-015 on October 23, 2025 and closed it on May 21, 2026. NHTSA's investigations file lists the 2019–2020 Acura ILX for it and links recall 25V-859 to it.
Updated daily from NHTSA's investigations file
Key facts
- NHTSA number
- PE25-015 (also written PE25015)
- 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 May 21, 2026
- Opened
- Closed
- Vehicle or equipment manufacturer
- Honda (American Honda Motor Co.)
- Component
- Service Brakes, Hydraulic — Foundation Components — Master Cylinder
- Recall linked by NHTSA
- 25V-859: Reduced Brake Function, reported
- Vehicles and equipment
- 2019–2020 Acura ILX
NHTSA's summary
As NHTSA's Office of Defects Investigation wrote it for Preliminary Evaluation PE25-015.
try.vin does not copy NHTSA's investigation documents; NHTSA's investigation record lists the ones NHTSA has published.
On October 23, 2025, the Office of Defects Investigation (ODI) opened Preliminary Evaluation PE25015 after receiving complaints concerning a loss of brake assist in 2019-2020 MY Acura ILX vehicles. These complainants alleged master cylinder failures resulting in soft pedal feel or the brake pedal intermittently going to the floor. These failures could result in extended braking distance increasing the risk of a crash. Honda found that residual plasticizer in the brake reservoir hose could contaminate the brake fluid. This contaminated brake fluid was then absorbed by the secondary cup seal, causing it to swell. Engine heat during operation could further expand the swollen seal, allowing brake fluid to pass. Brake fluid bypassing the master cylinder cup seals can reduce brake-pedal firmness and increase stopping distance. On April 08, 2026, Honda filed Recall 25V-859, recalling all 2016-2020 MY Acura ILX vehicles produced from October 9, 2014, to January 29, 2020. Under the recall, the dealer will replace the brake master cylinder with redesigned inner cup seals made of a different material, providing improved sealing capability. In view of Honda filing Recall 25V-859 addressing the subject of this investigation, ODI is closing this Preliminary Evaluation. NHTSA reserves the right to take additional action if warranted by future circumstances. 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 PE25-015. 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.
Acura
All Acura recallsWhat 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.
Acura VIN check: decode a VIN to see its year, make and model.
Sources
NHTSA's investigation record for PE25-015
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.