Motor Vehicle Defect Petitions; Denials

Denial of Motor Vehicle Defect Petition, DP26-004

SUPPLEMENTARY INFORMATION:

Introduction

Interested persons may petition NHTSA requesting that the Agency initiate an investigation to determine whether a motor vehicle or an item of replacement equipment does not comply with an applicable motor vehicle safety standard or contains a defect that relates to motor vehicle safety. 49 U.S.C. 30162(a)(2); 49 CFR 552.1. Upon receipt of a properly filed petition, the Agency conducts a technical review of the petition, material submitted with the petition, and any additional information. 49 U.S.C. 30162(a)(2); 49 CFR 552.6. The technical review may consist solely of a review of information already in the possession of the Agency, or it may include the collection of information from a motor vehicle manufacturer and other sources. After conducting the technical review and considering appropriate factors, which may include, but are not limited to, the nature of the complaint, allocation of Agency resources, Agency priorities, the likelihood of uncovering sufficient evidence to establish the existence of a defect and the likelihood of success in any necessary enforcement litigation, the Agency will grant or deny the petition. See 49 U.S.C. 30162(a)(2); 49 CFR 552.8.

Background Information

The Office of Defects Investigation (ODI) received a petition on December 22, 2025, requesting a defect investigation into the hydraulic control unit (HCU) for the Anti-lock Braking System (ABS) on the MY 2010 Ford Fusion Hybrid.

Summary of Petition

The petition alleges that an illuminated ABS MIL is associated with a failure of the ABS HCU, resulting in ABS malfunction, loss of traction and electronic stability control functions, and reduced braking performance, particularly on slippery road surfaces.

Office of Defects Investigation Analysis

ODI conducted an analysis of complaints submitted to ODI for the subject vehicle population along with data submitted by Ford. The Petitioner alleged that the condition in the subject vehicles was comparable to the defect addressed by NHTSA recall No. 19V904, which covered certain MY 2006-2010 Ford Fusion, Mercury Milan, and Lincoln MKZ vehicles. The population of this recall consisted of the non-hybrid variants of these models. The recall addressed a defect where the ABS valves in the HCU could remain stuck open due to a chemical reaction with aged DOT 3 brake fluid, potentially causing extended brake pedal travel and increasing the risk of a crash. ⁽¹⁾ No visual or audible warning was presented to the driver in this scenario.

The MY 2010 Ford Fusion Hybrid is equipped with a different brake apply system in which the traditional hydraulic (friction) brakes are blended with the hybrid regenerative brake system. In this system, the brake master cylinder is electrically activated and provides force feedback through the brake pedal to the driver. Unlike the recalled models, Petitioner's 2010 Ford Fusion Hybrid would not experience the same defect, as a stuck-open normally closed valve within its ABS HCU does not result in increased brake pedal travel. This condition is further supported by the relative complaint rates in the two populations: ODI found the complaint rate of the recalled MY 2010 Fusion vehicles was six times higher than that of the subject MY 2010 Fusion Hybrid vehicles, which supports a significant difference in the design and performance of the brake system and components.

As the Petitioner stated, most of the subject hybrid vehicle VOQs cited an illuminated ABS MIL. The vehicles in 19V904 did not present the driver with an illuminated MIL or associated diagnostic trouble code (DTC). Since the MY 2010 Ford Fusion Hybrid presented with a brake MIL, the failure mode differs from that of the non-hybrid population, which did not trigger an illuminated warning light. Additionally, given the age of the subject vehicles (MY 2010), the low complaint volume is consistent with expected wear and tear rather than an actionable safety defect trend.

Due to the age of the vehicles and the lack of an actionable safety defect trend-stemming from differences in the ABS HCU between non-hybrid MY 2010 Ford Fusions and Petitioner's hybrid MY 2010 Ford Fusion-ODI is denying this Defect Petition as it has not found an unreasonable risk to highway safety. The Agency reserves the right to take additional action if warranted by future circumstances. To review the reports cited in the Closing Resume ODI Report Identification Number document, go to NHTSA.gov.

Authority: 49U.S.C. 30162(d) and 49 CFR Part 552; delegation of authority at 49 CFR 1.95(a). ⁽²⁾

⁽¹⁾  DOT 3 brake fluid is a conventional, glycol-ether-based hydraulic fluid used to transfer force from the brake pedal to a vehicle's brakes.

⁽²⁾  The authority to determine whether to approve or deny defect petitions under 49 U.S.C. & 30162(d) and 49 CFR part 552 has been further delegated to the Associate Administrator for Enforcement.