C1A00: How to Diagnose & Fix — Stability Control System Fault

The Terrain Response system on the LR3/LR4 develops faults where mode selection fails or the system defaults to General mode only. The rotary selector switch wears out internally, and the shift motor on the transfer case can fail. Corroded connectors at the transfer case are a common root cause. The vehicle remains drivable in General mode but loses off-road capability.

F56 generation Coopers experience electric power steering rack failures. The EPS motor or control module within the rack fails, causing sudden loss of power assist or intermittent heavy steering. This is a safety concern as it can happen while driving.

The 2012 Mk3 Focus was the first Focus with a fully electric rack-mounted power steering assist (EPAS). The torque/position sensor and motor assembly inside the rack, and the power steering control module (PSCM) integrated with it, fail intermittently - often heat-soaked on long drives or hot days. The dash shows "Power Steering Assist Fault - Service Now", the wheel goes heavy with no warning, and steering no longer self-centers. Failures are frequently intermittent at first (assist returns after a key cycle) and then become permanent. Because the assist motor is integral to the rack, Ford's repair is a complete steering gear replacement. Unlike the Fusion/Taurus/Flex family, which got NHTSA recall 15V340 for the same motor-sensor defect, the Focus was never recalled despite hundreds of NHTSA complaints, and was instead the subject of a class-action suit covering 2012-2014 Focus and Focus Electric.

Early Eclipse Cross models with Forward Collision Mitigation brake hard for objects that are not there. This is not just owner perception — NHTSA recall 18V620000 covers 2018-2019 Mitsubishi vehicles whose FCM-ECU software applies braking for longer than needed even after a pedestrian is no longer detected, with the stated consequence that drivers brake harder in response and increase rear-end collision risk. Companion recall 18V621000 covers a hydraulic unit ECU software defect that may prevent automatic emergency braking, ABS, electronic stability control and Brake Auto Hold from working properly. Owner complaints go beyond the recall scope: filings describe adaptive cruise control triggering FCM braking when cresting hills with nothing ahead, and repeated multi-warning-light events with hard braking recurring several times a year despite dealer repairs. The camera-and-radar fusion is sensitive to road crown, overhead signs and reflective surfaces, and the system's brake authority is high enough that a false trigger at highway speed is genuinely hazardous.