The wrong EGR sensor is installed on the vehicle. Verify with the manufacturer for the latest.
A bad ignition module is present.
This is a manufacturer specific fault code and can be used for several different faults, depending upon what the manufacturer wants to use it for. The Powertrain Control Module (PCM) communicates over the Serial Communication Protocol (SCP) bus network, or J1850 bus. This is a medium-speed bus communication system and is fault tolerant, which means any type of intermittent/loose connection at these controllers will cause this code to set in memory, but will still operate, provided a data path is available. When the PCM is unable to communicate with any other controller at any time while the ignition switch is turned on, code U1009 will set. This is the typical reason for this code to set.
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