GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Cadillac 🢒 2002 🢒 Seville 🢒 Engine 🢒 Engine Controls - 4.6L 🢒 DTC P0130 or P0150

Circuit Description

The heated oxygen sensor (HO2S) is a sensor used to detect the oxygen content in the exhaust. The powertrain control module (PCM) supplies the sensor with a signal circuit and a ground circuit. The PCM supplies a bias voltage between the circuits. The sensor varies the voltage based on the oxygen content in the exhaust. When the exhaust stream is lean (more oxygen), the sensor produces a low voltage signal. When the exhaust stream is rich (less oxygen), the sensor produces a high voltage signal. The PCM monitors the HO2S signal during Closed Loop. In order to correct for rich or lean conditions, the PCM adjusts the injector pulse width. This DTC indicates that the signal frequency of the HO2S indicates an active sensor (Closed Loop), but the amplitude (voltage) of the signal remains within an incorrect range.

Conditions for Running the DTC
    • DTCs P0101, P0102, P0103, P0106, P0107, P0108, P0116, P0117, P0118, P0121, P0122, P0123, P0125, P0131, P0132, P0133, P0134, P0151, P0152, P0153, P0154, P0201-P0208, P1133, P1134, P1153, or P1154 are not set.
    • The coolant temperature is more than 75°C (176°F).
    • The engine is running for 120 seconds (2 minutes).
    • The system voltage is between 10-18 volts.
    • The predicted oxygen sensor (O2) heater temperature is 600°C (1,112°F).
    • The traction control is inactive.
    • The Catalyst Protection Mode is inactive.
    • The engine speed is between 500-5,000 RPM.
    • The mass air flow (MAF) is between 3-30 g/s.
    • All conditions above are met for 5 seconds.
    • The Closed Loop fuel control is enabled.

Conditions for Setting the DTC
    • The vehicle is in Closed Loop fuel control, based on the HO2S voltages switching from below 350 mV to above 500 mV.
    • The PCM monitors the HO2S voltages for 120 seconds (2 minutes).
    • During the 120 second monitoring period, the voltage remains within 350-500 mV for approximately 16 seconds.

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.

Diagnostic Aids

If the problem is intermittent, refer to Intermittent Conditions .

Step

Action

Value(s)

Yes

No

Schematic Reference: Engine Controls Schematics

1

Did you perform the Diagnostic System Check-Engine Controls?

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Go to Step 2

Go to Diagnostic System Check - Engine Controls

2
  1. With the engine at operating temperature, raise, and hold the engine speed above 1,200 RPM for 2 minutes.
  2. Observe the affected HO2S voltage display on the scan tool.

Does the scan tool indicate HO2S voltage varying outside the specified values?

350-500 mV

Go to Step 3

Go to Step 4

3
  1. Review and record scan tool Failure Records data.
  2. Operate the vehicle within the Failure Records conditions.
  3. With the scan tool, observe the Specific DTC Information for this DTC until the test runs.

Does the scan tool indicate that this test passed?

--

Go to Intermittent Conditions

Go to Step 4

4
  1. Disconnect the affected HO2S harness connector.
  2. Turn ON the ignition, with the engine OFF.
  3. Jumper the HO2S high signal circuit and low signal circuit in the harness connector (PCM side).
  4. Observe the affected HO2S voltage display on the scan tool.

Does the scan tool indicate an HO2S voltage below the specified value?

150 mV

Go to Step 6

Go to Step 5

5
  1. Turn OFF the ignition.
  2. Disconnect the PCM connector C1. Refer to Powertrain Control Module Replacement .
  3. Test for the following conditions:
    4. • Open high signal circuit
    • Open low signal circuit
    • Poor terminal connections at the PCM
  4. If a condition is found, repair as necessary. Refer to Wiring Repairs or Connector Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 9

Go to Step 8

6
  1. Inspect for poor terminal connections at the HO2S harness connector. Refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems.
  2. If a condition is found, repair as necessary. Refer to Connector Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 9

Go to Step 7

7

Replace affected HO2S. Refer to Heated Oxygen Sensor Replacement - Bank 1 Sensor 1 or Heated Oxygen Sensor Replacement - Bank 2 Sensor 1 .

Did you complete the replacement?

--

Go to Step 9

--

8

Replace the PCM. Refer to Powertrain Control Module Replacement .

Did you complete the replacement?

--

Go to Step 9

--

9
  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 10

Go to Step 2

10

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