2020 Subaru Impreza

Reference complaint no.11684658 confirmed. From email from Tech representative "VDC HYDRAULIC UNIT REPLACEMENT. IT IS AN INTERNAL FAILURE OF THE ABS CONTROL UNIT. THERE ARE SENSORS INSIDE THAT MEASURE BRAKE LINE PRESSURE. THE LEFT FRONT SENSOR IS STUCK AT NEGATIVE 59 BAR. SHOULD BE ZERO AT REST. NOTHING TO DO WITH EYESIGHT THAT LIGHT WILL COME ON WHENEVER THERE IS A WARNING LIGHT ON." The modulator is a safety critical component which undergoes extensive life time testing, one out of 4 pressure sensors should not fail during vehicle life time.

A loud rumbling noise and vibration occurs while braking at high speed. Braking force seems unaffected but the noise in concerning. Upon inspection and a test drive, Subaru confirmed the issued and noticed uneven brake pad wear on the front brakes and leakage in the front caliper. Subaru recommended replacement of front calipers, pads, and rotors. Subaru replaced pads and rotors. The noise continues to occur occassionally. Subaru is recommending replacement of front brake calipers but is unable to replace them due to a shortage. I am concerned the brakes or other components may fail due to unusual wear. No inspection by police or insurance has been completed. No warning lights occurred, only the noise and vibration during braking.

I believe this article describes the cause of the issue. Thankfully the vehicle was parked in my driveway, and did not roll into the street or harm any people, but it could have. 2020 Subaru Impreza Wrx Service Brakes related problems https://www.carproblemzoo.com/subaru/imprezawrx/2020/2020-subaru-imprezawrx-service-brakes-problems.php

WHO: DAUGHTER 16YO (DRIVER), FATHER (FRONT PASSENGER SEAT), DAUGHTER 14YO (DRIVER SIDE REAR SEAT). VEHICLE: 2020 SUBARU IMPREZA WHAT: SUBARU ANTI-COLLISION ENGAGED UNNECESSARILY WHEN: 0704 EST 14 MAY 2021 WHERE: 41°43'07.4"N 81°14'08.3" MY 16YO DAUGHTER WAS DRIVING AND I WAS IN THE PASSENGER SEAT. WE WERE HEADING EAST ON E WALNUT STREET AT APPROXIMATELY 35 MPH ABOUT TO CROSS THE S STATE STREET INTERSECTION. THERE WERE NO VEHICLES OR OBSTRUCTIONS IN FRONT OF THE VEHICLE. THE SUBARU ANTI-COLLISION BEGAN TO ALERT AND ABRUPTLY STOPPED THE VEHICLE. THE VEHICLE BEHIND US HAD TO BRAKE ABRUPTLY BUT DID NOT HIT US. I BELIEVE THIS WAS DUE TO THE SUN BEING LOW ON THE HORIZON AND DIRECTLY IN THE CAMERA'S VIEW. THIS IS THE FOURTH TIME THE ANTI-COLLISION HAS ENGAGED UNNECESSARILY. THE EVENTS PRIOR TO THIS, I WAS DRIVING LESS THAN 35 MPH IN MODERATE TO HEAVY TRAFFIC AND THE VEHICLE IN FRONT OF ME WAS EXITING THE ROAD CAUSING THE ANTI-COLLISION BRAKING TO ENGAGE.