1994 econoline fuel system electrical
Escort/Tracer, Crown Victoria/Grand Marquis, Thunderbird/Cougar, Town Car, 5.0L Mustang, Aerostar, Ranger, Explorer, E-Series
- The electrical circuit of the Inertia Fuel Shutoff (IFS) switch may vary per engine/vehicle application.
- Inertia Fuel Shutoff (IFS) switch with fuel reset light (F-Series and Bronco).
- Inertia Fuel Shutoff (IFS) switch with fuel reset light (Town Car).
Fuel Pump Circuit Operation
When the ignition is switched to the ON position, it turns the EEC Power Relay on. The EEC Power Relay provides power to the EEC-IV processor and the control side of the fuel pump relay. Power for the fuel pump is supplied through a fuse link or high current fuse attached to the starter solenoid (battery side). From the fuse link or high current fuse, current flow is through the fuel pump relay and Inertia Fuel Shutoff (IFS) switch to the fuel pump. The IFS switch is a safety device used to shut off the fuel pump in the event of a collision. If the IFS switch is "tripped," it must be reset by depressing the white or red button on the top of the switch. The fuel pump relay is controlled by the Powertrain Control Module (PCM).
When the ignition switch is turned to the ON position, the fuel pump will operate. If the ignition switch is not turned to the START position, the PCM will shut the fuel pump off after approximately one second. The PCM will operate the fuel pump when the ignition is in the START position to provide fuel while cranking.
After the engine starts, the PCM will continue to operate the fuel pump unless the engine stops, engine speed drops below 120 rpm, or the IFS switch is "tripped."
Note: Grounding the FP lead at the DLC will allow the pump to run continuously with the ignition switch on.