Circuit Description
The WIF sensor is attached to the fuel filter. The WIF sensor sends a signal to the electronic
control module (ECM) when a set volume of water has accumulated in the fuel filter.
Component Location
This fault code indicates that water has been detected in the water separation fuel filter. Drain
the water from the fuel filter.
If this fault code is active and there is no water in the fuel filter, a malfunctioning Water-In-Fuel
sensor is a likely cause.
Reference the appropriate OEM wiring diagram when troubleshooting circuits that utilize wiring
supplied by the OEM.
The WIF sensor is installed in the bottom or side of the fuel filter, which is located on the intake
side of the cylinder head approximately midengine.
Cummins ISB CM550 (1990-94) Fault Code: 415-SW PID: 100 SPN: 100 FMI: 1 Oil Pressure – Engine Protection With An Oil Pressure Switch
Cummins ISB CM550 (1990-94) Fault Code: 415-SN PID: 100 SPN: 100 FMI: 1 Oil Pressure – Engine Protection
Cummins ISB CM550 (1990-94) Fault Code: 391 PID: SID 017 SPN: 632 FMI: 11 Fuel Pump Relay Coil Supply Circuit
Cummins ISB CM550 (1990-94) Fault Code: 387 PID: SID 232 SPN: FMI: 1 Accelerator Position Sensor Circuit
Cummins ISB CM550 (1990-94) Fault Code: 387 PID: 91 SPN: FMI: 1 Accelerator Position Sensor Circuit
Cummins ISB CM550 (1990-94) Fault Code: 387 PID: SID 232 SPN: FMI: 3 Accelerator Position Sensor Circuit
