Powertrain Malfunction (Wrench) Warning Indicator
WARNING: This page is about a different car, the 2006 Mercury Milan, 2006 Lincoln Zephyr, and 2006 Ford Fusion. However, it is still accessible from the selected car via links, so may be relevant.
The PCM and the transmission control module (TCM) monitor the powertrain system and provide the instrument cluster with the operating status over the communication network. When a system concern is detected, the PCM and/or the TCM provide the instrument cluster with a signal commanding the instrument cluster to illuminate the powertrain malfunction (wrench) warning indicator.