GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Holden 🢒 2008 🢒 Viva 🢒 Safety and Security 🢒 Supplemental Inflatable Restraints 🢒 DTC P0133

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 Descriptor

DTC P0133: HO2S Slow Response Sensor 1

Diagnostic Fault Information

Circuit

Short to Ground

Open/High Resistance

Short to Voltage

Signal Performance

HO2S 1 Signal

P0131, P0137

P0134, P0140

P0132, P0138

P0133

Low Reference

--

P0134, P0140

P0132, P0138

P0133

Circuit Description

The heated oxygen sensors (HO2S) are used for fuel control and catalyst monitoring. Each HO2S compares the oxygen content of the surrounding air with the oxygen content of the exhaust stream. When the engine is started, the control module operates in an Open Loop mode, ignoring the HO2S signal voltage while calculating the air-to-fuel ratio. The control module supplies the HO2S with a reference, or bias voltage of about 450 mV. While the engine runs, the HO2S heats up and begins to generate a voltage within a range of 0-1,000 mV. This voltage will fluctuate above and below the bias voltage. Once sufficient HO2S voltage fluctuation is observed by the control module, Closed Loop is entered. The control module uses the HO2S voltage to determine the air-to-fuel ratio. An HO2S voltage that increases above bias voltage toward 1,000 mV indicates a rich fuel mixture. An HO2S voltage that decreases below bias voltage toward 0 mV indicates a lean fuel mixture.

The heating elements inside each HO2S heat the sensor to bring the sensor up to operating conditions faster. This allows the system to enter Closed Loop earlier and the control module to calculate the air-to-fuel ratio sooner.

The HO2S utilizes the following circuits:

    • A signal circuit
    • A low reference circuit
    • An ignition 1 voltage circuit
    • A heater control circuit

Conditions for Running the DTC
    • DTCs P0107, P0108, P0117, P0118, P0122, P0123, P0131, P0132, P0134, P0135, P0171, P0172, P0201, P0202, P0203, P0204, P0300, P0336, P0337, P0351, P0352, P0400, P0404, P0405, P0406, P0444, P0445, P0506, P0507, P1402, P1403, and P1404 are not set.
    • The startup engine coolant temperature is greater than 70°C (158°F).
    • The ignition 1 voltage is greater than 10 volts.
    • The engine has been operating for more than 1 minute.
    • The evaporative emissions (EVAP) system purge is less than 20 percent.
    • The fuel system is in closed loop.
    • The engine airflow is between 8-30 g/s.
    • The engine speed is between 1,500 and 3,000 RPM.
    • The DTC runs once per ignition cycle when the above conditions are met for 2 seconds.

Conditions for Setting the DTC
    • The ECM detects that the HO2S 1 rich-to-lean average response time is less than 90 milliseconds or lean-to-rich average response time is more than 125 milliseconds.
        Or
    • The ECM detects that the HO2S 1 rich-to-lean or lean-to-rich switches are less than 10.
        Or
    • The ECM detects that the HO2S 1 signal spends twice the amount of time in the rich region as compared to the lean region or the HO2S 1 signal spends twice the amount of time in the lean region as compared to the rich region.

Action Taken when the DTC Sets

DTC P0133 is a Type B DTC.

Conditions for Clearing the MIL/DTC

DTC P0133 is a Type B DTC.

Reference Information

Schematic Reference

Engine Controls Schematics

Connector End View Reference

Component Connector End Views

Electrical Information Reference

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

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification
  1. Engine running, observe the DTC information parameter with a scan tool. Verify other DTCs are not set.
    2. ⇒If any DTCs are set, refer to Diagnostic Trouble Code (DTC) List - Vehicle.
  2. Observe the DTC information parameter with a scan tool. DTCs P0133 or P0139 should not set.
  3. Operate the vehicle within the Conditions for Running the DTC to verify the DTC does not reset. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

Circuit/System Testing
  1. Verify none of the following conditions exist:
    2. • Lean or rich fuel injectors--Refer to Fuel Injector Balance Test with Special Tool.
    • Water intrusion in the HO2S harness connector
    • HO2S wiring harness damage
    • Incorrect RTV sealant
    • Low or high fuel system pressure--Refer to Fuel System Diagnosis.
    • Fuel that is contaminated--Refer to Alcohol/Contaminants-in-Fuel Diagnosis.
    • Fuel saturation of the evaporative emission (EVAP) canister
    • Exhaust leaks near the HO2S.
    • Engine vacuum leaks
    • Engine oil consumption--Refer to Symptoms - Engine Mechanical.
    • Engine coolant consumption--Refer to Loss of Coolant.
         ⇒If you find any of the above conditions, repair as necessary.
  2. If all conditions test normal, test or replace the HO2S.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    •  Heated Oxygen Sensor 1 Replacement
    •  Control Module References for engine control module replacement, setup, and programming