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DTC Descriptions

  1. DTC P0130: HO2S-11 Circuit Malfunction

    DTC P0130 indicates voltage from HO2S-11 is consistently approximately 0.3 volt. Possible causes are:
    • HO2S-11 circuit is open or shorted to GND.
    • Faulty HO2S-11 sensor.

    For DTC P0130, HO2S-11 PID should vary between 0.0-0.3 volt and 0.6-1.0 volt while engine is operating at 2000 RPM. Also, a change from rich to lean should occur more than 5 times during a period of 10 seconds at an engine speed of 2000 RPM.

  2. DTC P0131: HO2S-11 Circuit Low Voltage

    DTC P0131 indicates HO2S-11 signal rich values and lean values to PCM are both on the low side. Possible causes are:
    • Faulty front HO2S.
    • Faulty front HO2S heater.
    • Incorrect fuel pressure.
    • Faulty fuel injectors.
    • Intake air leaks.

    For DTC P0131, HO2S-11 PID should vary between 0.0-0.3 volt and 0.6-1.0 volt while engine is operating at 2000 RPM.

  3. DTC P0132: HO2S-11 Sensor Circuit High Voltage

    DTC P0132 indicates HO2S-11 signal rich values and lean values to PCM are both on the high side. Possible causes are:
    • Faulty front HO2S.
    • Faulty front HO2S heater.
    • Incorrect fuel pressure.
    • Faulty fuel injectors.

    For DTC P0132, HO2S-11 PID should vary between 0.0-0.3 volt and 0.6-1.0 volt while engine is operating at 2000 RPM.

  4. DTC P0133: HO2S-11 Circuit Slow Response

    DTC P0133 indicates HO2S-11 signal cycling time is more than specified time. Possible causes are:
    • HO2S-11 circuit is open, or shorted to GND or VPWR.
    • Faulty front HO2S.
    • Faulty front HO2S heater.
    • Incorrect fuel pressure.
    • Faulty fuel injectors.
    • Intake air leaks.
    • Exhaust gas leaks.
    • Faulty PCV valve.
    • Faulty Mass Air Flow (MAF) sensor.

    For DTC P0133, an HO2S-11 PID should change from rich to lean more than 5 times during 10 seconds with engine running at 2000 RPM.

  5. DTC P0134: HO2S-11 Circuit No Activity Detected

    DTC P0134 indicates an excessively high voltage from HO2S-11 is sent to PCM. Possible causes are:
    • HO2S-11 circuit is open or shorted to VPWR.
    • Faulty front HO2S.

    For DTC P0134, HO2S-11 PID should vary between 0.0-0.3 volt and 0.6-1.0 volt while engine is operating at 2000 RPM.

  6. DTC P0135: HO2S-11 Heater Circuit Malfunction

    DTC P0135 indicates improper current amperage is drawn through front HO2S heater from PCM. Possible causes are:
    • Front HO2S heater circuit is open, or shorted to GND or VPWR.
    • Faulty front HO2S heater.

    For DTC P0135, front HO2S heater resistance should be 2.3-4.3 ohms at 77°F (25°C).

  7. DTC P0137: HO2S-12 Circuit Low Voltage

    DTC P0137 indicates HO2S-12 signal rich values and lean values to PCM are both on the low side. Possible causes are:
    • Faulty rear HO2S.
    • Faulty rear HO2S heater.
    • Incorrect fuel pressure.
    • Faulty fuel injectors.
    • Intake air leaks.

    For DTC P0137, HO2S-12 PID should vary between 0.0-0.3 volt and 0.6-1.0 volt with engine running at 2000 RPM.

  8. DTC P0138: HO2S-12 Circuit High Voltage

    DTC P0138 indicates HO2S-12 signal rich values and lean values to PCM are both on the high side. Possible causes are:
    • Faulty rear HO2S.
    • Faulty rear HO2S heater.
    • Incorrect fuel pressure.
    • Faulty fuel injectors.

    For DTC P0138, HO2S-12 PID should vary between 0.0-0.3 volt and 0.6-1.0 volt with engine running at 2000 RPM.

  9. DTC P0139: HO2S-12 Circuit Slow Response

    DTC P0139 indicates when it takes more than the specified time for HO2S-12 to respond between rich and lean conditions. Possible causes are:
    • HO2S-12 circuit is open, or shorted to GND or VPWR.
    • Faulty rear HO2S.
    • Incorrect fuel pressure.
    • Faulty fuel injectors.
    • Intake air leaks.

    For DTC P0139, HO2S-12 PID should vary between 0.0-0.3 volt and 0.6-1.0 volt with engine running at 2000 RPM.

  10. DTC P0140: HO2S-12 Circuit No Activity Detected

    DTC P0140 indicates an excessively high voltage from HO2S-12 is sent to PCM. Possible causes are:
    • HO2S-12 circuit is open or shorted to VPWR.
    • Faulty rear HO2S.

    For DTC P0140, HO2S-12 PID should vary between 0.0-0.3 volt and 0.6-1.0 volt with engine running at 2000 RPM.

  11. DTC P0141: HO2S-12 Heater Circuit Malfunction

    DTC P0141 indicates improper current amperage is drawn through rear HO2S heater from PCM. Possible causes are:
    • Rear HO2S heater circuit is open, or shorted to GND or VPWR.
    • Faulty rear HO2S heater.

    For DTC P0141, rear HO2S heater resistance should be 2.3-4.3 ohms at 77°F (25°C).

  12. DTC P0171: System Too Lean (Bank 1)

    HO2S-11 and Mass Air Flow (MAF) sensor circuits are monitored by PCM. PCM then compares input data to theoretical mixture ratio. PCM then tries to compensate for difference in actual and theoretical. DTC P01171 indicates amount of compensation is too large (actual mixture is too lean). Possible causes are:
    • Intake air leaks.
    • Damaged or disconnected front HO2S or circuit.
    • Plugged injectors.
    • Fuel pressure regulator stuck open.
    • Exhaust gas leaks.
    • Incorrect fuel pressure.
    • Lack of fuel.
    • Faulty MAF sensor.
    • Faulty PCV system.
    • Oil overfill.
    • Incorrect cam timing.
    • Low Compression.
    • Faulty coil and secondary side of the ignition system.

    For DTC P0171, with ignition on and engine running at idle, fuel pressure should be 34 psi (235 kpa). HO2S-11 PID should vary between 0.0-0.3 volt and 0.6-1.0 volt with engine running at 2000 RPM. MAF PID reading with engine running at idle should be 1.0-1.7 volts. MAF PID reading with engine running at 2500 RPM should be 1.7-2.3 volts.

  13. DTC P0172: System Too Rich (Bank 1)

    HO2S-11 and Mass Air Flow (MAF) sensor circuits are monitored by PCM. PCM then compares input data to theoretical mixture ratio. PCM then tries to compensate for difference in actual and theoretical. DTC P0172 indicates when amount of compensation is too large (actual mixture is too rich). Possible causes are:
    • Damaged or disconnected HO2S-11 sensor or circuit.
    • Exhaust gas leaks.
    • Incorrect fuel pressure.
    • Leaking injectors.
    • Fuel pressure regulator leaking.
    • Faulty MAF sensor.
    • Faulty PCV system.
    • Oil overfill.
    • Incorrect cam timing.
    • Low compression.
    • Faulty coil and secondary side of ignition system.

    For DTC P0172, with ignition on and engine running at idle, fuel pressure should be 34 psi (235 kpa). HO2S-11 PID should vary between 0.0-0.3 volt and 0.6-1.0 volt with engine running at 2000 RPM. MAF PID reading with engine running at idle should be 1.0-1.7 volts. MAF PID reading with engine running at 2500 RPM should be 1.7-2.3 volts.

  14. DTC P1148: Closed Loop Control Malfunction

    Mass Air Flow (MAF) sensor, Camshaft Position (CMP) sensor, and HO2S-11 circuits are monitored by PCM. DTC P1148 indicates closed loop control function does not operate even when vehicle is driving in specified condition. Possible causes are:
    • HO2S-11 circuit is open, or shorted to GND or VPWR.
    • Faulty front HO2S.
    • Faulty front HO2S heater.

    For DTC P1148, HO2S-11 PID voltage should rise to more than 0.70 volt at least once with engine running at 2000 RPM. HO2S-11 PID voltage should decrease to less than 0.21 volt at least once with engine running at 2000 RPM.

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