FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
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P1861






P1861-SIPHON LINE DISCONNECTED





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

- When Monitored:
With the ignition key on.

- Set Condition:
Powertrain Control Module (PCM) compares the primary tank level with the secondary tank level. If the PCM detects the primary side is lower than the secondary side by a calibrated amount the DTC will set.





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

1. DTC IS ACTIVE

NOTE: Diagnose any Fuel Level DTCs before proceeding with this test.

NOTE: The following test must be performed on both Fuel Level Sensors.

1. Inspect the Fuel Pump Module harness connectors for any corrosion or damage.
2. Start the engine and allow it to reach normal operating temperature.

WARNING: When the engine is operating, do not stand in direct line with the fan. Do not put your hands near the pulleys, belts or fan. Do not wear loose clothing. Failure to follow these instructions may result in possible serious or fatal injury.

3. With the scan tool, select View DTCs.

Is the status Active for this DTC?

Yes

- Go To 2

No

- Perform the CHECKING FOR AN INTERMITTENT DTC diagnostic procedure. Checking for an Intermittent DTC.

2. FUEL TANK INSPECTION
1. Inspect both sides of the Fuel Tank for any damage that may restrict the Fuel Level Sensor float.

Were any problems found?

Yes

- Replace the Fuel Tank as necessary.
- Perform the PCM VERIFICATION TEST. PCM Verification Test.

No

- Go To 3

3. FUEL LEVEL SIGNAL CIRCUIT SHORTED TO GROUND
1. Turn the ignition off.
2. Disconnect the Fuel Pump Module harness connector.
3. Measure the resistance between ground and each Fuel Level Signal circuit at the Fuel Pump Module harness connector.

Is the resistance below 100 Ohms?

Yes

- Repair the Fuel Level Signal circuit for a short to ground.
- Perform the PCM VERIFICATION TEST. PCM Verification Test.

No

- Go To 4

4. FUEL LEVEL SIGNAL CIRCUIT OPEN OR HIGH RESISTANCE
1. Disconnect the Cluster harness connector.
2. Measure the resistance of each Fuel Level Signal circuit from the Fuel Pump Module harness connector to the Cluster harness connector.

Is the resistance below 5.0 Ohms?

Yes

- Go To 5

No

- Repair the Fuel Level Signal circuit for an open circuit or high resistance.
- Perform the PCM VERIFICATION TEST. PCM Verification Test.

5. (Z906) GROUND CIRCUIT OPEN OR HIGH RESISTANCE
1. Measure the resistance between ground and the (Z906) Ground circuit in the Fuel Pump Module harness connector.

Is the resistance below 5.0 Ohms?

Yes

- Go To 6

No

- Repair the (Z906) Ground circuit for an open circuit or high resistance.
- Perform the PCM VERIFICATION TEST. PCM Verification Test.

6. FUEL TANK AND SIPHON HOSE INSPECTION

WARNING: The fuel system is under a constant pressure even with the engine off. Before opening the fuel system, the fuel pressure must be released. Failure to follow these instructions can result in possible serious or fatal injury.

1. Inspect the following components:
- Siphon hose for restrictions or being disconnected.
- Siphon Inlet and Outlet tube on the Fuel Modules for restrictions.
- Fuel Pump Inlet Strainers for restrictions.
- Fuel Tank for any obstructions or deformities.
- Fuel Pump Module Float arm for damage.

Were any problems found?

Yes

- Repair or replace as necessary.
- Perform the PCM VERIFICATION TEST. PCM Verification Test.

No

- Replace the Fuel Level Sensor.
- Perform the PCM VERIFICATION TEST. PCM Verification Test.