U1411

U1411-IMPLAUSIBLE FUEL VOLUME SIGNAL RECEIVED







Theory of Operation

The PCM receives:

- Wheel speed and wheel distance CAN bus messages from the Anti-lock Brake module.

- A/C Pressure, Ambient Air Temperature and Fuel Level CAN bus messages from the Totally Integrated Power Module.

- When Monitored:
With the ignition on, battery voltage between 9 and 16 volts, and engine run time greater than 3 seconds.

- Set Condition:
The PCM either doesn't receive a bus message or receives an implausible bus message from the Totally Integrated Power Module (TIPM).





Refer to Electrical/Electronic Control Modules for diagnostic procedures and for further possible causes.

1. ACTIVE DTC
1. Ignition on, engine not running.
2. With a scan tool, select View DTCs.

Is the DTC Active at this time?

Yes

- Go to 2

No

- Refer to the *CHECKING FOR AN INTERMITTENT DTC Diagnostic Procedure. Checking for an Intermittent DTC

2. CAN C BUS DTCS ALSO ACTIVE
1. With a scan tool check for DTCs in the TIPM.

Are any CAN C related DTCs Active at this time?

Yes

- Diagnose and repair the DTC(s).
- Perform PCM Verification Test. PCM Verification Test

No

- Go to 3

3. FUEL LEVEL SENSOR




1. Turn the ignition off.
2. Disconnect the Fuel Pump Module 1 harness connector.
3. Ignition on, engine not running.
4. Using a fused jumper wire, jump the (P37) Switch Return circuit to the (N4) Fuel Level Sensor Signal 1 circuit in the Fuel Pump Module 1 harness connector.

Did the Fuel gauge level change from empty to full?

Yes

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

No

- Go to 4

4. (N4) FUEL LEVEL SIGNAL 1 CIRCUIT SHORTED TO GROUND




1. Turn the ignition off.
2. Disconnect the C7 TIPM harness connector.
3. Measure the resistance between ground and the (N4) Fuel Level Signal 1 circuit in the Fuel Pump Module 1 harness connector.

Is the resistance below 100 ohms?

Yes

- Repair the short to ground in the (N4) Fuel Level Signal 1 circuit.
- Perform PCM Verification Test. PCM Verification Test

No

- Go to 5

5. (N4) FUEL LEVEL SIGNAL 1 CIRCUIT SHORTED TO THE (P37) SWITCH RETURN CIRCUIT




1. Measure the resistance between the (N4) Fuel Level Signal 1 circuit and the (P37) Switch Return circuit from the Fuel Pump Module 1 harness connector.

Is the resistance below 5.0 ohms?

Yes

- Repair the short between the (P37) Switch Return circuit and the (N4) Fuel Level Signal 1 circuit.
- Perform PCM Verification Test. PCM Verification Test

No

- Go to 6

6. EXCESSIVE RESISTANCE IN THE (N4) FUEL LEVEL SIGNAL CIRCUIT




1. Measure the resistance of the (N4) Fuel Level Signal 1 circuit from the Fuel Pump Module harness connector to the C7 TIPM harness connector.

Is the resistance below 5.0 ohms?

Yes

- Go to 7

No

- Repair the excessive resistance in the (N4) Fuel Level Signal circuit.
- Perform PCM Verification Test. PCM Verification Test

7. EXCESSIVE RESISTANCE IN THE (P37) SWITCH RETURN CIRCUIT




1. Measure the resistance of the (P37) Switch Return circuit from the Fuel Pump Module harness connector to the C7 TIPM harness connector.

Is the resistance below 5.0 ohms?

Yes

- Go to 8

No

- Repair the excessive resistance in the (P37) Switch Return circuit.
- Perform PCM Verification Test. PCM Verification Test

8. POWERTRAIN CONTROL MODULE (PCM)
1. Using the wiring diagram/schematic as a guide, inspect the wiring and connector at the Powertrain Control Module (PCM).
2. Look for any chafed, pierced, pinched, or partially broken wires.
3. Look for broken, bent, pushed out or corroded terminals. Verify that there is good pin to terminal contact in the Powertrain Control Module connectors.
4. Search for any Technical Service Bulletins that may apply.

Were there any problems found?

Yes

- Repair as necessary.
- Perform PCM Verification Test. PCM Verification Test

No

- Replace and program the Powertrain Control Module.
- Perform PCM Verification Test. PCM Verification Test