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Home >> Mercury >> 2009 >> Sable Base, AWD >> Repair and Diagnosis >> External Pages >> Different car >> Section 1255 (Engine Controls - Powertrain DTC Charts & Descriptions (Except Diesel & Hybrid)) >> DTC Diagnosis >> DTC U0300: - Internal Control Module Software Incompatibility
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DTC U0300: - Internal Control Module Software Incompatibility

WARNING: This page does not describe the selected car, but rather 32 other vehicles, including the 2009 Mercury Mountaineer, 2009 Mercury Milan, 2009 Mercury Mariner, 2009 Mercury Grand Marquis, and 2009 Lincoln Town Car. However, it is still accessible from the selected car via links, so may be relevant.
DTC U0300: - INTERNAL CONTROL MODULE SOFTWARE INCOMPATIBILITY

Description:  This DTC indicates there are incompatible software levels within the powertrain control module (PCM) that control the electronic throttle control (ETC) system. The ETC system uses multiple microprocessors within the PCM, each having its own software level and function. The microprocessors must have the correct level of software in order to communicate and function together.
Possible Causes: 
Diagnostic Aids:  Verify the PCM is at the latest calibration level.
Application  Key On Engine Off  Key On Engine Running  Continuous Memory 
All - - GO to Pinpoint Test QE .