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Alternative Fuel Control Module: Description and Operation

NOTE: The descriptions and specifications contained were in effect at the time this information was approved for printing. Ford Motor Company reserves the right to discontinue models at any time, or change specifications or design without notice and without incurring obligation.

Alternative Fuel Control Module (AFCM)
The Alternative Fuel Control Module (AFCM) is incorporated within the Compuvalve and allows communication between the Compuvalve and the Powertrain Control Module (PCM). The AFCM communicates desired operating mode, ALT or GAS, to the PCM. This allows information to be shared between modules and facilitates troubleshooting. When ALT mode is selected and operating conditions are satisfactory, the Compuvalve, through the AFCM, signals the PCM to turn off the gasoline fuel injectors. During alternative fuel operation, if the fuel source drops below a specified amount, the Compuvalve through the AFCM signals the PCM to turn on the gasoline fuel injectors while the Compuvalve shuts off alternative fuel. This allows smooth switching of fuel systems.