Check Fuel Cap Indicator
WARNING: This page is about a different car, the 2003 Ford Pickup, 2003 Ford F550 Super Duty, 2003 Ford F450 Super Duty, 2003 Ford Excursion, and 2003 Ford Cab & Chassis. However, it is still accessible from the selected car via links, so may be relevant.
The check fuel cap indicator is used to indicate significant leaks in the fuel tank evaporative system due to a loose fuel cap. Fuel tank pressure is monitored by the PCM and once a leak is detected, the PCM signals a fault to the instrument cluster via the SCP network. Once the PCM has detected a loose fuel cap and the check fuel cap indicator is illuminated, the check fuel cap indicator will remain illuminated until the fuel cap is secured and the vehicle has been running for several minutes or the ignition has been cycled once.