Fuel Filler Cap: Description and Operation

FUEL CAP OFF INDICATOR LAMP

The Fuel Cap Off Indicator Lamp (FCIL) is an output signal that is controlled by the PCM and will illuminate when the strategy determines that there is a failure in the vapor management system due to the fuel filler cap not being sealed properly. This would be detected by the inability to pull vacuum in the fuel tank, after a fueling event.

NOTE: The Escape, Freestar/Monterey, Mustang, Thunderbird, Town Car, Lincoln LS6/LS8, Expedition and Navigator do not have a dedicated (separate) output wire from the PCM to the instrument cluster. The PCM commands the FCIL on and off through the BUS +/- circuits (SCP).