DTC U0439: Invalid Data Received from the All Terrain Control Module: Action

This DTC sets if the hill descent control request or the terrain mode request messages from the AWD module contains invalid data. RETRIEVE and DIAGNOSE all AWD module DTCs. REFER to Four-Wheel Drive Systems or Power Transfer unit articles. . If no DTCs are set in the AWD module, the condition may be caused by an intermittent concern. SET the ignition to OFF. DISCONNECT and INSPECT all AWD module electrical connectors for corrosion, bent pins, pushed-out pins and spread terminals. REPAIR as necessary.