DTC U0420: Invalid Data Received From Power Steering Control Module: Action
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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 appropriate Power Steering System article. If the diagnostic scan tool cannot communicate with the PSCM, REFER to appropriate 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.