ALT Fuel Injectors
WARNING: This page is about a different car, the 2004 Ford Pickup Heritage. However, it is still accessible from the selected car via links, so may be relevant.
The alternative fuel control module (AFCM) contains the drivers for both the ALT fuel and gasoline injectors. In CNG mode, the AFCM disables the gasoline fuel injectors and enables the ALT fuel injectors. The AFCM controls the ALT fuel injectors based on the corresponding input signals from the powertrain control module (PCM) fuel injector drivers. The ALT fuel injectors require an increased driver due to the higher operating current requiring greater heat dissipation.