What Does Code U0100 Mean? U0100 stands for “Lost Communication with ECM/PCM.” The Engine Control Module (ECM) is the computer responsible for controlling the engine. The ECM communicates with other ...

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The Engine Control Module, or ECM, directly controls the engine. Still, it can’t do that properly without the Transmission Control Module or TCM and PCM, which work together and exchange information.

Did you use an OBD2 scanner on your car to figure out why the check engine light is on, only to get the P0303 code? Here's what it means, plus possible fixes.

There are two key numbers you'll find on your car -- the VIN and the Engine number -- and both play key roles in your car's past and future.