Cummins ISX11.9 CM2250 – Service Manual 019-127   Water in Fuel Sensor

General Information

TOC

The water-in-fuel sensor separator is located at the base of the suction side fuel filter. The water-in-fuel sensor sends a signal to the electronic control module (ECM) when a set volume of water has accumulated in the fuel filter. The water-in-fuel circuit contains two wires, the water-in-fuel return wire and the water-in-fuel signal wire. 

Use the following procedure to drain the water from the filter. Refer to Procedure 006-066 in Section 6.

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Resistance Check

TOC

Disconnect the engine harness from the ECM. Disconnect the water-in-fuel sensor from the OEM harness. Check for dirty or damaged pins on the ECM connector and the water-in-fuel sensor connector of the OEM harness.

Use the following procedure for general inspection techniques. Refer to Procedure 019-361 in Section 19.

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 CAUTION 

To reduce the possibility of pin and connector damage, use test lead, Part Number 3822758, when taking a measurement.

Measure the resistance of the water-in-fuel sensor return circuit at the ECM connector of the wiring harness and the water-in-fuel sensor connector of the OEM wiring harness.

The multimeter must show a closed circuit (10 ohms or less).

If more than 10 ohms are measured, there is an open circuit in the return wire.

Troubleshoot all interconnects for an open circuit. Repair or replace the wiring harness. Refer to Procedure 019-071 in Section 19.

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Measure the resistance of the water-in-fuel sensor signal circuit at the ECM connector of the wiring harness and the water-in-fuel sensor connector of the OEM wiring harness.

The multimeter must show a closed circuit (10 ohms or less).

If more than 10 ohms are measured, there is an open circuit in the signal wire. Troubleshoot all interconnects for an open circuit.  Repair or replace the wiring harness. Refer to Procedure 019-071 in Section 19.

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Last Modified:  06-Jul-2010