P0193
P0193-FUEL PRESSURE SENSOR HIGH
For a complete wiring diagram, refer to the Wiring Information Electrical Diagrams. Electrical Diagrams
Theory of Operation
The Electronic Control Module (ECM) provides a 5-volt supply to the Fuel Rail Pressure Sensor (FPS). The ECM also provides a ground on the sensor return circuit. The Fuel Rail Pressure Sensor provides a signal to the ECM on the Fuel Rail Pressure Sensor Signal circuit. This sensor signal voltage changes based on the pressure in the fuel rail. The ECM will detect a low signal voltage at low rail pressures. The ECM will detect a high signal voltage during high rail pressure conditions. The ECM will light the MIL lamp immediately after the diagnostic runs and fails. During this time the customer may experience a power and or speed derate. The ECM will turn off the MIL light after the diagnostic runs and passes in 4 consecutive drive cycles.
- When Monitored:
With the ignition on and battery voltage greater than 10.4 volts.
- Set Condition:
The circuit voltage to the Electronic Control Module (ECM) is above a calibrated threshold for a certain period of time.
Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. Pre-Diagnostic Troubleshooting Procedure.
1.
NOTE: If there are any 5-volt supply DTCs present, repair those DTCs before proceeding.
1. Turn the ignition on.
2. With the scan tool, record all Freeze frame data.
3. With the scan tool, erase DTCs.
4. Turn the ignition off for 30 seconds.
5. Turn the ignition on.
6. With the scan tool, read DTCs.
Did the DTC reset?
Yes
- Go To 2
No
- Perform the INTERMITTENT CONDITION diagnostic procedure. Intermittent Condition Test.
2. (K181) SIGNAL CIRCUIT SHORTED TO VOLTAGE
1. Turn the ignition off.
2. Disconnect the Fuel Pressure Sensor harness connector.
3. Turn the ignition on.
4. Measure the voltage of the (K181) FPS Signal circuit at the Fuel Pressure Sensor harness connector.
Is the reading above 5.01 volts?
Yes
- Repair the short to voltage in the (K181) FPS Signal circuit.
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Powertrain Verification Test.
No
- Go To 3
3. (K181) SIGNAL CIRCUIT SHORTED TO THE (F855) 5-VOLT SUPPLY CIRCUIT
1. Turn the ignition off.
2. Disconnected ECM C1 harness connector.
3. Measure the resistance between the (K181) FPS Signal circuit and the (F855) 5-Volt Supply circuit at the Fuel Pressure Sensor harness connector.
Is the resistance below 10k Ohms?
Yes
- Repair the short between the (K181) FPS Signal circuit and the (F855) 5-Volt Supply circuit.
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Powertrain Verification Test.
No
- Go To 4
4. (K181) SIGNAL CIRCUIT OPEN
1. Measure the resistance of the (K181) FPS Signal circuit between the Fuel Pressure Sensor harness connector and the ECM C1 harness connector.
Is the resistance below 10.0 Ohms?
Yes
- Go To 5
No
- Repair the open or high resistance in the (K181) FPS Signal circuit.
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Powertrain Verification Test.
5. (K916) SENSOR GROUND OPEN
1. Measure the resistance of the (K916) Sensor Ground circuit between the Fuel Pressure Sensor harness connector and the ECM C1 harness connector.
Is the resistance below 10.0 Ohms?
Yes
- Go To 6
No
- Repair the open or high resistance in the (K916) Sensor Ground circuit.
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Powertrain Verification Test.
6. FUEL PRESSURE SENSOR
1. Turn the ignition off.
2. Reconnect the ECM C1 harness connector.
3. Reconnect the Fuel Pressure Sensor harness connector.
4. Turn the ignition on.
5. With the scan tool, erase DTCs.
6. While monitoring scan tool, connect a jumper between the (K181) FPS Signal circuit and the (K916) Sensor Ground circuit at the Fuel Pressure Sensor harness connector.
Does the DTC P0192 set?
Yes
- Replace the Fuel Pressure Sensor.
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Powertrain Verification Test.
No
- Replace and program the Electronic Control Module (ECM).
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Powertrain Verification Test.