GM Service Manual Online
For 1990-2009 cars only

Diagnostic Instructions

    • 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.

DTC Descriptors

DTC P0182: Fuel Temperature Sensor Circuit Low Voltage

DTC P0183: Fuel Temperature Sensor Circuit High Voltage

Diagnostic Fault Information

Circuit

Short to Ground

High Resistance

Open

Short to Voltage

Signal Performance

Fuel Temperature Signal

P0182

P0183²

P0183

P0183

--

Low Reference

--

²

P0183

¹

--

¹ Opens fuse in 12-volt circuit

² Temperature is skewed and may not have any codes

Typical Scan Tool Data

Fuel Temperature Sensor

Circuit

Short to Ground

High Resistance

Open

Short to Voltage

Operating Conditions: The Ignition ON, with the Engine OFF

Parameter Normal Range: -30 to +120°C (-22 to +248°F)

Fuel Temperature Signal

120°C (248°F)

Varies¹

-40°C (-40°F)

-40°C (-40°F)

¹ Skewed sensor

Circuit/System Description

The fuel temperature sensor is a thermistor. The engine control module (ECM) supplies the fuel temperature sensor a bias voltage of 5 volts on the signal circuit and also provides a low reference circuit to the sensor. When the fuel temperature sensor is cold, the resistance is high. The fuel temperature sensor signal voltage remains near the 5 volt bias voltage cold and decreases as the sensor warms. The ECM monitors the fuel temperature sensor signal circuit in order to calculate the temperature of the fuel entering the engine.

Conditions for Running the DTC

P0182

    • The ignition is ON.
    • DTC P0182 runs continuously within the enabling conditions.

P0183

    • The ignition is ON.
    • DTC P0183 runs continuously within the above enabling conditions.

Conditions for Setting the DTC

P0182

The fuel temperature sensor is more than 120°C (248°F) for 2 seconds.

P0183

The fuel temperature sensor is less than -30°C (-22°F) for 2 seconds.

Action Taken When the DTC Sets

DTCs P0182 and P0183 are Type A DTCs.

Conditions for Clearing the MIL/DTC

DTCs P0182 and P0183 are Type A DTCs.

Diagnostic Aids

    • A short to a separate or different 5-volt source may set a DTC P0183.
    • A skewed sensor could result in poor driveability concerns.

Reference Information

Schematic Reference

Engine Controls Schematics

Connector End View Reference

Engine Control Module Connector End Views

Electrical Information Reference

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

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

    •  Scan Tool Data List
    •  Scan Tool Output Controls
    •  Scan Tool Data Definitions

Circuit/System Verification

  1. Turn ON the ignition and observe the Fuel Temperature Sensor parameter with a scan tool. The fuel temperature parameter should be within the operating range.
  2. 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.

Circuit/System Testing

  1. Ignition OFF, disconnect the harness connector at the fuel temperature sensor.
  2. Ignition OFF for 90 seconds, test for less than 5 ohms of resistance between the low reference circuit terminal 2 and ground.
  3. If greater than the specified value, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the ECM.
  4. Ignition ON, verify the scan tool Fuel Temperature Sensor parameter is less than -39°C (-38°F).
  5. If greater than the specified value, test the signal circuit terminal 1 for a short to ground. If the circuit tests normal, replace the ECM.
  6. Install a 3A fused jumper wire between the signal circuit terminal 1 and the low reference circuit terminal 2. Verify the scan tool Fuel Temperature parameter is greater than 120°C (248°F).
  7. If less than the specified value, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the ECM.
  8. If all circuits test normal, test fuel temperature sensor.

Component Testing

Measure and record the resistance of the fuel temperature sensor at various ambient temperatures and compare those measurements to the Temperature vs. Resistance table. Refer to Temperature Versus Resistance .

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    •  Fuel Temperature Sensor Replacement
    •  Control Module References for ECM replacement, setup, and programming