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Powertrain Control Module (PCM) Inputs

The Engine Controller (ECM) located in the Powertrain Control Module (PCM) shares two signals with the transaxle controller TCM. These two signals are the vehicle speed signal (received from the vehicle speed sensor), and an ignition voltage signal.

The vehicle speed signal is used by the transaxle control module to determine vehicle speed for transaxle shifting.

The ignition voltage signal is the turn On signal for the transaxle control module.