P2266

P2266-WATER IN FUEL SENSOR CIRCUIT LOW





For a complete wiring diagram refer to the Wiring Information Electrical Diagrams.

Theory of Operation

The water in fuel sensor is attached to the fuel filter. The Powertrain Control Module (ECM) provides a 5-volt reference signal to the water in fuel sensor. When the water collected in the fuel filter covers the sensor probes, the water in fuel sensor then pulls the 5-volt reference voltage to ground indicating high water accumulation in the fuel filter. The ECM illuminates the MIL lamp immediately after the diagnostic runs and fails. The ECM turns off the MIL lamp after the diagnostic runs and passes in 4 consecutive drive cycles.

- When Monitored:
Ignition on.

- Set Condition:
Low voltage detected at the WIF signal circuit at the ECM.





Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. Pre-Diagnostic Troubleshooting Procedure

1. WATER IN FUEL SENSOR
1. Turn the ignition off.
2. Disconnect the Water in Fuel Sensor harness connector.
3. Ignition on, engine not running.

NOTE: Check connectors - Clean/repair as necessary.

4. Measure the voltage between the (G123) Water in Fuel Signal circuit and the (K914) Sensor ground circuit of the WIF Sensor harness connector.

Is the voltage between 4.5 and 5.5 volts?

Yes

- Replace the Water in Fuel Sensor.
- Perform POWERTRAIN VERIFICATION TEST - 6.7L. Powertrain Verification Test

No

- Go To 2

2. (G123) WIF SIGNAL CIRCUIT SHORTED TO (K914) SENSOR GROUND CIRCUIT
1. Disconnect the C1 ECM harness connector.

NOTE: Check connectors - Clean/repair as necessary.

2. Measure the resistance between the (G123) WIF Signal circuit and the (K914) Sensor ground circuit of the sensor harness connector.

Is the resistance less than 10 ohms?

Yes

- Repair the short between the (G123) WIF Signal circuit and the (K914) Sensor ground circuit.
- Perform POWERTRAIN VERIFICATION TEST - 6.7L. Powertrain Verification Test

No

- Go To 3

3. (G123) WIF SIGNAL CIRCUIT SHORTED TO GROUND
1. Measure the resistance between ground and the (G123) WIF Signal circuit at the sensor harness connector.

Is the resistance less than 10 ohms?

Yes

- Repair the short to ground in the (G123) WIF Signal circuit.
- Perform POWERTRAIN VERIFICATION TEST - 6.7L. Powertrain Verification Test

No

- Go To 4

4. ECM
1. Reconnect the C1 ECM harness connector.
2. Measure the resistance between the (G123) WIF Signal circuit and the (K914) Sensor ground circuit of the sensor connector.

Is the resistance less than 10 ohms?

Yes

- Replace the ECM.
- Perform POWERTRAIN VERIFICATION TEST - 6.7L. Powertrain Verification Test

No

- Test Complete.