The Office of Defects Investigation (ODI) has received 4 VOQs and a few Early Warning Reporting field reports alleging a loss of brake performance in MY2019 Acura ILX vehicles. The MY2020 Acura ILX is also included within the scope of the investigation due to the shared brake system design with MY2019.Consumers allege that when attempting apply the brake, the brake pedal pushed to the floor with a loss of braking force.? There was no detectability prior to the occurrence.? Failure or malfunction of the braking system can result in extended stopping distance, which may lead to an increased risk of a crash resulting in injury and/or property damage. ODI is opening this Preliminary Evaluation (PE) to determine the scope and severity of the potential problem and to fully assess the potential safety-related issues. To review the ODI reports cited in the opening Resume ODI Report Identification Number document, go to NHTSA.gov.