• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
• Review Strategy Based Diagnosis for an overview of the diagnostic approach.
• Diagnostic Procedure Instructions provides an overview of each diagnostic category.

The fuel pressure/temperature sensor transmits fuel pressure and temperature information by serial data using the Society of Automotive Engineers (SAE) J2716 Single Edge Nibble Transmission (SENT) protocol. The fuel pressure/temperature sensor internal microprocessor allows 4 separate sensor outputs from one 3 wire sensor. The engine control module (ECM) supplies the fuel pressure/temperature sensor with a 5 V reference circuit, a low reference circuit, and an asynchronous signal/serial data circuit. The asynchronous signal means communication is only going from the fuel pressure/temperature sensor to the ECM. The ECM decodes the serial data signal into separate voltages.

• The engine is running for greater than 1 min.
• The commanded fuel pressure rate of change, increase or decrease, is less than 3 MPa (435 PSI) for greater than or equal to 1.25 s.
• The DTC runs continuously within the enabling conditions.

• The engine is cranking or running.
• The DTC runs continuously within the enabling condition.

The difference between the commanded high pressure and the measured high pressure is greater than or less than a predefined threshold for greater than or equal to 1.5 s.

The ECM detects that the fuel pressure/temperature sensor signal voltage is low for greater than 30 s with the engine running or greater than 10 s with the engine cranking.

• DTCs P0191, P0192, are Type A DTCs.
• A message center or an indicator may display Reduced Engine Power.

DTCs P0191, P0192 are Type A DTCs.

• A high resistance condition on the fuel pressure/temperature sensor circuits could cause a DTC to set.
• Inspect for a contaminated fuel system.

Engine Controls Schematics

Master Electrical Component List

Powertrain Component Views

Fuel System Description

• Circuit Testing
• Connector Repairs
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Control Module References for scan tool information

1. Ignition » On / Vehicle » In Service Mode
2. Verify there are no DTCs set related to the following component/system:5V Reference
• If any of the DTCs are set

  Refer to:Diagnostic Trouble Code (DTC) List - Vehicle

• If none of the DTCs are set
3. Verify there are no DTCs set related to the following component/system:B310 Fuel Pressure/Temperature Sensor
• If other DTCs are set—With DTC P0191 set.

  Refer to Circuit/System Testing.

• If only DTC P0191 is set&No other DTCs related to the concerned component are set.

  Replace the component:B310 Fuel Pressure/Temperature Sensor

• If none of the DTCs are set
4. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.
5. Verify that no DTCs are set.
• If any of the DTCs are set

  Refer to Circuit/System Testing.

• If none of the DTCs are set
6. All OK.

1. Ignition OFF, and all vehicle systems OFF, disconnect the harness connector at B310 Fuel Pressure/Temperature Sensor. It may take up to 2 min for all vehicle systems to power down.
2. Test for less than 5 Ω between the low reference circuit terminal 1 and ground.
• If 5 Ω or greater
1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Test for less than 2 Ω in the low reference circuit end to end.
• If 2 Ω or greater, repair the open/high resistance in the circuit.
• If less than 2 Ω, replace the K20 Engine Control Module.
• If less than 5 Ω
3. Ignition ON.
4. Test for 4.8–5.2 V between the 5 V reference circuit terminal 3 and ground.
• If less than 4.8 V
1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Test for infinite resistance between the 5 V reference circuit and ground.
• If less than infinite resistance, repair the short to ground on the circuit.
• If infinite resistance
3. Test for less than 2 Ω in the 5 V reference circuit end to end.
• If 2 Ω or greater, repair the open/high resistance in the circuit.
• If less than 2 Ω, replace the K20 Engine Control Module.
• If greater than 5.2 V
1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module, ignition ON.
2. Test for less than 1 V between the 5 V reference circuit and ground.
• If 1 V or greater, repair the short to voltage on the circuit.
• If less than 1 V, replace the K20 Engine Control Module.
• If between 4.8–5.2 V
5. Test for 4.8–5.2 V between the signal circuit terminal 2 and ground.
• If less than 4.8 V
1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Test for infinite resistance between the signal circuit and ground.
• If less than infinite resistance, repair the short to ground on the circuit.
• If infinite resistance
3. Test for less than 2 Ω in the signal circuit end to end.
• If 2 Ω or greater, repair the open/high resistance in the circuit.
• If less than 2 Ω, replace the K20 Engine Control Module.
• If greater than 5.2 V
1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module, ignition ON.
2. Test for less than 1 V between the signal circuit and ground.
• If 1 V or greater, repair the short to voltage on the circuit.
• If less than 1 V, replace the K20 Engine Control Module.
• If between 4.8–5.2 V
6. Replace the B310 Fuel Pressure/Temperature Sensor.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

• Fuel Rail Pressure Sensor Replacement for B310 Fuel Pressure/Temperature Sensor.
• Control Module References for control module replacement, programming and setup.