The Powertrain Control Module (PCM) is an advanced version of the ECU, encompassing broader control over the powertrain system. In addition to managing the engine, the PCM oversees the transmission, emissions, and other critical systems. By integrating multiple functions into one unit, the PCM enhances efficiency and performance in modern vehicles. Check Engine Light: A persistent check engine light could indicate a problem with the ECU, PCM, or ECM. Use a diagnostic tool to retrieve error co...