GM Service Manual Online
For 1990-2009 cars only

Object Number: 550694  Size: MF
Engine Controls Components
Fuel Temperature Controls, ITS Motor
OBD II Symbol Description Notice
Handling ESD Sensitive Parts Notice
Handling ESD Sensitive Parts Notice

Circuit Description

The fuel temperature sensor is a thermistor which controls the signal voltage to the powertrain control module (PCM). When the fuel is cold, the sensor resistance is high, therefore the PCM will see a high signal voltage. As the fuel warms, the sensor resistance becomes less and the voltage drops. The fuel temperature sensor is integrated with the optical sensor.

Conditions for Running the DTC

The ignition is ON.

Conditions for Setting the DTC

    • The fuel temperature is more than 102°C (215°F).
    • The conditions were met for 2 seconds.

Action Taken When the DTC Sets

    • The PCM illuminates the malfunction indicator lamp (MIL) on the second consecutive drive trip the diagnostic runs and fails.
    • The PCM records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the Failure Records store this information. If the diagnostic reports a failure on the second consecutive drive trip, the Freeze Frame records the operating conditions at the time of failure and updates the Failure Records.

Conditions for Clearing the MIL/DTC

    • The PCM will turn the MIL off after 3 consecutive trips without a fault condition.
    • A History DTC clears after 40 consecutive warm-up cycles, if this or any other emission related diagnostic does not report any failures.

Use a scan tool in order to clear the DTCs.

Diagnostic Aids

A scan tool reads the fuel temperature in degrees celsius.

An intermittent may be caused by:

    • Faulty connections
    • Rubbed-through wire insulation
    • A broken wire inside the insulation

Test Description

The numbers below refer to the step numbers on the Diagnostic Table.

  1. This step determines if DTC P0182 is a hard failure or an intermittent condition.

  2. This test will determine if signal circuit is shorted to ground.

Step

Action

Value(s)

Yes

No

1

Important: Before clearing any DTCs, use the scan tool Capture Info function in order to save the Freeze Frame and the Failure records for reference. The control module's data is deleted once the Clear Info function is used.

Was the Powertrain On-Board Diagnostic (OBD) System Check performed?

--

Go to Step 2

Go to Powertrain On Board Diagnostic (OBD) System Check

2

  1. Connect the scan tool.
  2. Start the engine.
  3. Monitor the Fuel Temp display on the scan tool.

Is the Fuel Temp more than the specified value?

102°C (215°F)

Go to Step 3

Go to Step 5

3

  1. Turn OFF the engine.
  2. Turn ON the ignition.
  3. Disconnect the optical/fuel temperature sensor connector.

Is the Fuel Temp less than or equal to the specified value?

17°C (63°F)

Go to Step 7

Go to Step 4

4

  1. Turn OFF the ignition.
  2. Disconnect the PCM connector with the fuel temperature signal circuit.
  3. Use the J 39200 DMM in order to measure the resistance across the fuel temperature signal circuit and a known good ground at the sensor harness connector.

Is the resistance at the specified value?

Go to Step 8

Go to Step 6

5

The DTC is intermittent. If no additional DTCs are stored, refer to Diagnostic Aids. If any additional DTCs were stored, refer to the applicable DTC tables first.

Are any additional DTCs stored?

--

Go to the applicable DTC Table

Go to Diagnostic Aids

6

Repair the short to ground in the fuel temperature signal circuit. Refer to Wiring Repairs in Wiring Systems.

Is the action complete?

--

Go to Step 9

--

7

Important: If the fuel injection pump is malfunctioning, the new injection pump must be timed. Refer to Fuel Injection Pump Timing Adjustment .

Replace the fuel injection pump. Refer to Fuel Injection Pump Replacement .

Is the action complete?

--

Go to Step 9

--

8

Important: The new PCM must be programmed. Refer to Powertrain Control Module Replacement/Programming .

Replace the PCM.

Is the action complete?

--

Go to Step 9

--

9

  1. Use a scan tool in order to clear the DTCs.
  2. Start the engine.
  3. Allow the engine to idle until the normal operating temperature is reached.
  4. Select DTC and the Specific DTC function.
  5. Enter the DTC number that was set.
  6. Operate the vehicle within the Conditions for Setting this DTC until the scan tool indicates the diagnostic Ran.

Does the scan tool indicate the diagnostic Passed?

--

Go to Step 10

Go to Step 2

10

Does the scan tool display any additional undiagnosed DTCs?

--

Go to the applicable DTC table

System OK