Circuit Description
The right/secondary fuel level sensor measures fuel level changes within the right/secondary fuel tank.
When the fuel level is high the sensor signal voltage is high. When the fuel level is low the sensor signal voltage is low.
The powertrain control module (PCM) uses inputs from the left/primary fuel level sensor and the right/secondary fuel level sensors in order to calculate the total fuel remaining in both fuel tanks. The PCM sends this information via class 2 to the IPC.
This diagnostic tests for a stuck right/secondary fuel level sensor signal. If the PCM determines that the fuel level (right tank) signal appears to be stuck based on a lack of signal variation expected during normal operation, this DTC sets.
Conditions for Running the DTC
The engine is operating.
Conditions for Setting the DTC
| • | The right/secondary fuel tank is not empty. |
| • | More than 241 km (150 mi) have been accumulated. |
| • | The PCM does not detect that the fuel level in the right/secondary fuel tank has not changed by at least 3.0 liters (0.80 gallons). |
OR
| • | The right/secondary fuel tank is not empty. |
| • | The left/primary fuel tank is not full. |
| • | Engine operating greater than 40 minutes. |
| • | The left/primary fuel tank does not achieve the top of its range. Observe, after operating the engine for greater than 40 minutes the fuel in the right/secondary fuel tank will transfer to the left/primary fuel tank. |
OR
| • | The right/secondary fuel tank is empty. |
| • | The left/primary fuel tank is full. |
| • | The fuel level in both fuel tanks does not change after traveling more than 284 km (200 mi). Observe, if the right/secondary fuel tank is empty, the left/primary fuel level should decrease after 284 km (200 mi). |
Action Taken When the DTC Sets
| • | The PCM stores the DTC information into memory when the diagnostic runs and fails. |
| • | The malfunction indicator lamp (MIL) will not illuminate. |
| • | The PCM records the operating conditions at the time the diagnostic fails. The PCM stores this information in the Failure Records. |
| • | The vehicle fuel gage displays empty. |
| • | The check gages indicator illuminates. |
| • | The driver information center displays the LOW FUEL message. |
Conditions for Clearing the MIL or DTC
| • | A history DTC will clear after 40 consecutive warm-up cycles, if no failures are reported by this or any other non-emission related diagnostic. |
| • | A last test failed, ore current DTC, will clear when the diagnostic runs and does not fail. |
| • | Use a scan tool in order to clear the MIL or DTC. |
Diagnostic Aids
Important: When inspecting for a deformed or warped fuel tank, measure the resistance of the suspect fuel level sensor at empty, with the sensor in the fuel tank, and again with the sensor removed from the fuel tank. The measured resistance values should be the same at empty. If the measured values are not the same, refer to Fuel Tank Replacement in Engine Controls.
Depending on the current fuel level, it may be difficult to locate a malfunctioning sending unit. The malfunction may only occur when the fuel level is full or near empty. The fuel sending unit may need to be removed for further diagnosis. A fuel level sensor that has an intermittent condition causes this DTC to set. Remove the fuel level sensor. Refer to Fuel Sender Assembly Replacement in Engine Controls in order to test the resistance of the sensor. The resistance of the sensor should change from 40 to 250 ohms. Replace the sensor if the resistance did not change or was out of range.
Step | Action | Values | Yes | No | ||||||
|---|---|---|---|---|---|---|---|---|---|---|
Schematic Reference: Instrument Cluster Schematics | ||||||||||
1 | Did you perform the IPC Diagnostic System Check? | -- | Go to Step 2 | |||||||
2 |
Did the voltage increase on the left/primary fuel level sensor and decrease on the right/secondary fuel level sensor after 20 minutes? | -- | Go to Step 4 | Go to Step 3 | ||||||
3 | Remove the right/secondary fuel tank. Refer to Fuel Tank Replacement in Engine Controls - 5.7L. Is there any fuel in the right/secondary fuel tank? | -- | Go to Fuel System Diagnosis in Engine Controls - 5.7L | Go to Step 4 | ||||||
4 |
Did you find and correct the condition? | -- | Go to Step 7 | Go to Step 5 -- | ||||||
5 |
Does the resistance change smoothly across the specified range? | 40-250ohms | Go to Diagnostic Aids | Go to Step 6 | ||||||
6 | Replace the right/secondary fuel sensor. Refer to Fuel Level Sensor Replacement - Right Side in Engine Control - 5.7L. Did you complete the replacement? | -- | Go to Step 7 | -- | ||||||
7 |
Does the DTC reset? | -- | Go to Step 2 | System OK | ||||||
