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√ Water In Fuel Indicator Sensor Circuit - Voltage Above Normal (Fault Code: SPN 97 - FMI 3)

SPN97 FMI3 (Cummins QSB3.3)

Figure 1.1 - Water In Fuel (SPN 97 - FMI 3)

Read More:
Fault Codes: Fuel Pressure Low (Detroit Diesel Diagnostic Link)
Throttle Position Signal Abnormal (Error Code: SPN 91 - FMI 8)

SPN 97 - FMI 3
Water-in-Fuel Indicator Sensor Circuit - Voltage Above Normal or Shorted to High Source. High voltage detected at the water-infuel circuit.
Figure 1.2 - Fault Code 0428 - Active (Lamp: Amber) 
Figure 1.3 - Displays the Fault Code 0428
Figure 1.4 - Fault Code 428 (Overview)

-Fault Code "Overview" displays the fault code, the cause of the fault, and the effect of the fault. This gives you a general understanding of what caused the fault and which fault to work on first. It also may contain the standard repair time (SRT) code for estimating the repair time.
-"Troubleshooting Steps" displays a list of corrective actions to take to troubleshoot the fault. Various levels of detail can be displayed for each troubleshooting step. Click the underlined text to view lists of steps to correct the fault.

Water-In-Fuel Sensor
Figure 1.5 - Water in Fuel Sensor

#Features and Parameters:
Select the feature name (Water in Fuel Sensor) and use the drop-down list in the ECM Value column to indicate whether a sensor is Installed or Not Installed.
Note: This feature requires a fuel filter with integral Water in Fuel Sensor built into the bottom of the filter.

The Water in Fuel Sensor protects the fuel system by alerting the vehicle operator that water has accumulated in the fuel filter and should be drained. The operator is warned of a high water condition by a flashing lamp on the dash, and fault code 428 "Water in fuel indicator high - maintenance" is logged.

The fuel filter removes emulsified and free water from the fuel as it passes through the filter media. The removed water is heavier than fuel and falls to the bottom of the filter canister where it accumulates.

The Water in Fuel Sensor is installed in the base of the fuel filter canister. The sensor consists of two metallic probes that sense the electrical conductivity of the surrounding solution. A change in conductivity can be detected when sufficient water accumulates around the probes and displaces the diesel fuel. When this happens the ECM lights the warning light on the dashboard.