DTC P1433 Without FFS
Circuit Description
The right fuel level sensor measures fuel level changes within the right 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 PCM uses inputs from the left fuel level sensor and the right fuel level sensor 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 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.
The left tank fuel pump also supplies a small amount of pressurized fuel to the right fuel tank siphon jet pump through the auxiliary fuel feed rear pipe. The pressurized fuel creates a venturi action inside the siphon jet pump. The venturi action causes the fuel to be drawn out of the right fuel tank. Fuel is then transferred from the right fuel tank to the left fuel tank through the auxiliary fuel return rear pipe. The fuel system is designed to maintain a greater level in the left fuel tank then the right fuel tank when the electric fuel pump is operating. The fuel transfer rate from the left fuel tank to the right fuel tank is less than the transfer rate from the right fuel tank to the left fuel tank. Therefore, with the electric fuel pump operating, the left fuel tank level should be higher than the right fuel tank level.
The fuel level in the fuel tanks equalize when the following occur:
| • | The electric fuel pump is not operating. |
| • | The fuel level is greater than 50 percent. |
Conditions for Running the DTC
The engine is operating.
Conditions for Setting the DTC
| • | The fuel level sensor 2 voltage is greater than 2.9 volts. |
| • | The above condition present for greater than 2.0 minutes. |
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 a 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 resistance 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. |
| • | The following occurs with this DTC set: |
| - | The vehicle fuel gage displays empty. |
| - | The check gages indicator illuminates. |
| - | The driver information center displays a message. |
| • | For an intermittent condition, refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems. |
The voltages in the Fuel Level Conversion Table are approximate values. Use this table to aid in diagnosis.
Test Description
The numbers below refer to the step numbers on the Diagnostic Table.
-
This step determines if the fault is present.
-
The fuel level sensor may only fail at a certain range. If you determine the condition is intermittent, inquire with the customer when the concern occurred. The concern may only happen when the vehicle is re-fueled or when the fuel level is close to empty.
Using the Freeze Frame and/or Failure Records data may aid in locating an intermittent condition. If you cannot duplicate the DTC, the information included in the Freeze Frame and/or Failure Records data can help determine how many miles since the DTC set. The Fail Counter and Pass Counter can also help determine how many ignition cycles the diagnostic reported a pass and/or a fail. Operate the vehicle within the same freeze frame conditions (RPM, load, vehicle speed, temperature etc.) that you observed. This will isolate when the DTC failed.
-
If the voltage goes low, this determines the circuits and the PCM are OK.
Step | Action | Values | Yes | No |
|---|---|---|---|---|
Schematic Reference: Instrument Cluster Schematics | ||||
1 | Did you perform the IPC Diagnostic System Check ? | -- | Go to Step 2 | |
Is the Fuel Level sensor right tank voltage above the specified value? | 2.9 V | Go to Step 4 | Go to Step 3 | |
Does the scan tool indicate that this diagnostic failed this ignition? | -- | Go to Step 4 | Go to Diagnostic Aids | |
4 |
Is the fuel level sensor voltage above the specified value? | 5 V | Go to Step 14 | Go to Step 5 |
Is the Fuel Level sensor voltage below the specified value? | 2.9 V | Go to Step 8 | Go to Step 6 | |
6 | Connect a jumper wire between the fuel level sensor signal circuit to a known good ground. Is the fuel level sensor voltage below the specified value? | 2.9 V | Go to Step 9 | Go to Step 7 |
7 |
Is the fuel level sensor signal circuit open? | -- | Go to Step 12 | Go to Step 15 |
8 |
Does the DMM display a resistance within the specified range? | 0-2 ohms | Go to Step 14 | Go to Step 10 |
9 |
Is the Fuel Level sensor ground circuit open? | -- | Go to Step 13 | Go to Step 15 |
10 | Inspect for poor connections at the fuel level sensor harness connector. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 17 | Go to Step 11 |
11 | Replace the fuel level sensor. Refer to Fuel Sender Assembly Replacement in Engine Controls. Did you complete the replacement? | -- | Go to Step 17 | -- |
12 | Repair the open fuel level sensor signal circuit. Refer to Wiring Repairs in Wiring Systems. Did you complete the repair? | -- | Go to Step 17 | -- |
13 | Repair the open fuel level sensor ground circuit. Refer to Wiring Repairs in Wiring Systems. Did you complete the repair? | -- | Go to Step 17 | -- |
14 | Repair the fuel level sensor signal circuit for a short to voltage. Refer to Wiring Repairs in Wiring Systems. Did you complete the repair? | -- | Go to Step 17 | -- |
15 | Inspect for poor connections at the PCM harness connector. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 17 | Go to Step 16 |
16 |
Important: Program the replacement PCM. Replace the PCM. Refer to Powertrain Control Module Replacement in Engine Controls. Did you complete the replacement? | -- | Go to Step 17 | -- |
17 |
Does the scan tool indicate that this test ran and passed? | -- | Go to Step 18 | Go to Step 2 |
18 | Select the Capture Info option and the Review Info option using the scan tool. Does the scan tool display any DTCs that you have not diagnosed? | -- | Go to the applicable DTC | System OK |
DTC P1433 W/FFS
Circuit Description
The right fuel level sensor measures fuel level changes within the right fuel tank and changes resistance based on fuel level. The powertrain control module (PCM) monitors changes in the resistance of the sensor to determine fuel level.
When the fuel tank is full, the sensor resistance is high, and the PCM senses high signal voltage. When the fuel tank is empty, the sensor resistance is low, and the PCM senses a low signal voltage.
The PCM uses inputs from the fuel level sensors to calculate the total fuel remaining in the fuel tanks. This information is then sent to the instrument panel cluster (IPC) via the class 2 serial data circuit.
When the PCM senses a signal voltage higher than the normal operating range of the sensor, this DTC sets.
Conditions for Running the DTC
The ignition is ON.
Conditions for Setting the DTC
| • | Fuel level sensor voltage for the right level sensor is above 2.9 volts. |
| • | The fuel level signal is greater than 98 percent. |
| • | The above conditions are present for greater than 2 minutes. |
Action Taken When the DTC Sets
| • | The DIC displays a LOW FUEL message. |
| • | The fuel gage defaults to empty. |
| • | The check gages indicator illuminates. |
| • | The PCM records the operating conditions at the time the diagnostic fails. The PCM displays the failure information in the Failure Records on the scan tool. |
Conditions for Clearing the DTC
| • | The DTC becomes history when the conditions for setting the DTC are no longer present. |
| • | The history DTC clears after 40 malfunction free warm-up cycles. |
| • | The PCM receives the clear code command from the scan tool. |
Diagnostic Aids
Use the Freeze Frame and/or Failure Records data in order to locate an intermittent condition. If you cannot duplicate the DTC, the information included in the Freeze Frame and/or Failure Records data may aid in determining the number of miles since the DTC set. The Fail Counter and Pass Counter can also aid in determining the number of ignition cycles that the diagnostic reported a pass and/or fail. Operate the vehicle within the same freeze frame conditions (RPM, load, vehicle speed, temperature, etc.). This will isolate when the DTC failed.
Refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems.
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 resistance values are not the same, refer to Fuel Tank Replacement in Engine Controls.
Test Description
The number below refers to the step number on the diagnostic table.
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
Schematic Reference: Instrument Cluster Schematics | ||||
1 | Did you perform the IPC Diagnostic System Check? | -- | Go to Step 2 | |
2 |
Does the scan tool indicate that the Fuel Tank Level Remaining parameter is greater than the specified value? | 98% | Go to Step 3 | Go to Diagnostic Aids |
Does the scan tool indicate that the Fuel Tank Level Remaining parameter is less than the specified value? | 4% | Go to Step 6 | Go to Step 4 | |
4 | Test the signal circuit of the fuel level sensor for an open, a high resistance, or for a short to voltage. Refer to Circuit Testing and to Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 12 | Go to Step 5 |
5 | Test the low reference circuit of the fuel level sensor for an open, a high resistance, or for a short to voltage. Refer to Circuit Testing and to Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 12 | Go to Step 9 |
6 | Test the signal circuit of the fuel level sensor for an open, a high resistance, or for a short to voltage between C402 and the fuel level sensor. Refer to Circuit Testing and to Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 12 | Go to Step 7 |
7 | Test the low reference circuit of the fuel level sensor for an open, a high resistance, or for a short to voltage between C408 and the fuel level sensor. Refer to Circuit Testing and to Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 12 | Go to Step 8 |
8 | Inspect for poor connections at the harness connector of the fuel level sensor. Refer to Testing for Intermittent Conditions and Poor Connections and to Connector Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 12 | Go to Step 10 |
9 | Inspect for poor connections at the harness connector of the PCM. Refer to Testing for Intermittent Conditions and Poor Connections and to Connector Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 12 | Go to Step 11 |
10 | Replace the fuel level sensor. Refer to Fuel Sender Assembly Replacement in Engine Controls. Did you complete the replacement? | -- | Go to Step 12 | -- |
11 |
Important: Program the replacement PCM. Replace the PCM. Refer to Powertrain Control Module Replacement in Engine Controls. Did you complete the replacement? | -- | Go to Step 12 | -- |
12 |
Does the DTC reset? | -- | Go to Step 2 | System OK |
