DTC U0420: Invalid Data Received From Power Steering Control Module: Action
WARNING: This page is about a different car, the 2018 Lincoln MKX and 2018 Ford Edge. However, it is still accessible from the selected car via links, so may be relevant.
This DTC sets if the SECM receives invalid data from the EPAS status message. Using a diagnostic scan tool, RETRIEVE and DIAGNOSE all PSCM DTCs. REFER to the Power Steering article. If the diagnostic scan tool cannot communicate with the PSCM, Refer to Module Communications Network article. If no DTCs are set in the PSCM, the concern may be intermittent. SET the ignition to OFF. DISCONNECT and INSPECT all PSCM electrical connectors and related in-line connectors for corrosion, bent pins, pushed-out pins and spread terminals. REPAIR as necessary.