GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Oldsmobile 🢒 2001 🢒 Aurora 🢒 Engine 🢒 Engine Controls - 3.5L 🢒 DTC P0452

Circuit Description

The fuel tank pressure sensor measures the pressure, or vacuum, in the fuel tank. The powertrain control module (PCM) provides the sensor with a reference voltage, a signal circuit, and a ground. The sensor returns a signal voltage to the PCM relative to the pressure in the fuel tank. The PCM should see a signal voltage increase as the pressure in the tank decreases (more vacuum). As the pressure in the tank increases (less vacuum), the PCM should see a signal voltage decrease. The PCM uses the sensor signal to test the integrity of the evaporative emission (EVAP) system. If the PCM detects a signal voltage that is too low, DTC P0452 will set.

Conditions for Running the DTC

The ignition is ON.

Conditions for Setting the DTC

The fuel tank pressure sensor voltage is less than 0.06 volt for at least 1 second.

Action Taken When the DTC Sets
    • The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
    • The control module records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the control module stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the control module records the operating conditions at the time of the failure. The control module writes the operating conditions to the Freeze Frame and updates the Failure Records.

Conditions for Clearing the MIL/DTC
    • The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
    • A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
    • A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
    • Clear the MIL and the DTC with a scan tool.

Step

Action

Values

Yes

No

Schematic Reference: Engine Controls Schematics

1

Did you perform the Diagnostic System Check-Engine Controls?

--

Go to Step 2

Go to Diagnostic System Check - Engine Controls

2

Is DTC P1639 also set?

--

Go to DTC P1639

Go to Step 3

3
  1. Turn ON the ignition with the engine OFF.
  2. Observe the fuel tank pressure display on the scan tool.

Does the scan tool indicate a fuel tank pressure less than the specified value?

0.10 V

Go to Step 5

Go to Step 4

4
  1. Review and record the scan tool Failure Records information.
  2. Operate the vehicle within the Failure Records conditions.
  3. Monitor the scan tool Specific DTC Information for this DTC until the test runs.

Does the scan tool indicate that this DTC reset?

--

Go to Step 5

Go to Intermittent Conditions

5
  1. Turn OFF the ignition.
  2. Disconnect the fuel tank pressure sensor connector.
  3. Turn ON the ignition with the engine OFF.
  4. Connect the appropriate jumper between the 5-volt reference B and sensor signal circuits.
  5. Observe the fuel tank pressure sensor voltage on the scan tool.

Does the scan tool indicate a fuel tank pressure sensor voltage near the specified value?

5 V

Go to Step 9

Go to Step 6

6
  1. Remove the jumper.
  2. Using a DMM , measure the voltage between the 5-volt reference B and sensor ground circuits.

Does the DMM indicate a voltage near the specified value?

5 V

Go to Step 7

Go to Step 8

7
  1. Test the fuel tank pressure signal circuit for the following conditions:
    2. • An open
    • A short to chassis or sensor ground
    • Faulty terminal connections at the PCM
  2. If a condition is found, repair as necessary. Refer to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 12

Go to Step 11

8
  1. Test the 5-volt reference circuit for the following conditions:
    2. • An open
    • Faulty terminal connections at the PCM
  2. If a condition is found, repair as necessary. Refer to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 12

Go to Step 11

9
  1. Test for poor terminal connections in the fuel tank pressure sensor harness connector.
  2. If a condition is found, repair as necessary. Refer to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 12

Go to Step 10

10

Replace the fuel tank pressure sensor. Refer to Fuel Tank Pressure Sensor Replacement .

Is the action complete?

--

Go to Step 12

--

11

Replace the PCM. Refer to Powertrain Control Module Replacement .

Is the action complete?

--

Go to Step 12

--

12
  1. Use the scan tool in order to clear the DTCs.
  2. Turn OFF the ignition for 30 seconds.
  3. Start the engine.
  4. Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text.

Does the DTC run and pass?

--

Go to Step 13

Go to Step 2

13

With a scan tool, observe the stored information, Capture info.

Does the scan tool display any DTCs that you have not diagnosed?

--

Go to Diagnostic Trouble Code (DTC) List

System OK