Important: Always perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
Circuit | Short to Ground | High Resistance | Open | Short to Voltage | Signal Performance |
---|---|---|---|---|---|
HO2S High Signal | P0131, P0132, P0134, P0137, P0140, P0151, P0154, P0157, P0160, P1133, P1153, P2A00, P2A01, P2A03, P2A04 | P0131, P0133, P0134, P0137, P0140, P0151, P0153, P0154, P0157, P0160, P1133, P1153, P2A00, P2A01, P2A03, P2A04 | P0131, P0133, P0134, P0137, P0140, P0153, P0154, P1133, P1153, P2A00, P2A01, P2A03, P2A04 | P0132, P0134, P0138, P0140, P0152, P0154, P0158, P0160, P1133, P1153, P2A00, P2A01, P2A03, P2A04 | P0133, P0134, P0140, P0153, P0160, P1133, P1153, P2A00, P2A01, P2A03, P2A04 |
HO2S Low Signal | P2A00, P2A01, P2A03, P2A04 | P0131, P0133, P0134, P0138, P0140, P0151, P0153, P0154, P0157, P0160, P1133, P1153, P2A00, P2A01 | P0131, P0133, P0134, P0138, P0140, P0153, P0154, P1133, P1153, P2A00, P2A01, P2A03, P2A04 | P0134, P0138, P0140, P0152, P0153, P0158, P0160, P1133, P1153, P2A00, P2A01, P2A03, P2A04 | P2A00, P2A01, P2A03, P2A04 |
Circuit | Normal Range | Short to Ground | Open | Short to Voltage |
---|---|---|---|---|
HO2S High Signal | 200-800 mV | 0 mV | Approximately 470 mV | Approximately 1,100 mV |
HO2S Low Signal | 200-800 mV | 455 mV | Approximately 450 mV | Approximately 445 mV |
Heated oxygen sensors (HO2S) are used for fuel control and post catalyst monitoring. Each HO2S compares the oxygen content of the surrounding air with the oxygen content in the exhaust stream. The HO2S must reach operating temperature to provide an accurate voltage signal. Heating elements inside the HO2S minimize the time required for the sensors to reach operating temperature. The control module supplies the HO2S with a reference, or bias, voltage of about 450 mV. When the engine is first started, the control module operates in Open Loop, ignoring the HO2S voltage signal. Once the HO2S reaches operating temperature and Closed Loop is achieved, the HO2S generates a voltage within a range of 0-1,000 mV that fluctuates above and below bias voltage. High HO2S voltage indicates a rich exhaust stream. Low HO2S voltage indicates a lean exhaust stream.
• | DTCs P0068, P0101, P0102, P0103, P0106, P0107, P0108, P0112, P0113, P0116, P0117, P0118, P0120, P0121, P0122, P0123, P0128, P0201, P0202, P0203, P0204, P0205, P0206, P0207, P0208, P0220, P0222, P0223, P0442, P0443, P0446, P0449, P0455, P0496, P1516, P2101, P2119, P2135, P2176 are not set. |
• | The Engine Coolant Temperature (ECT) Sensor parameter is more than 70°C (158°F). |
• | The Ignition 1 Signal parameter is between 10-18 volts. |
• | The Fuel Level Sensor parameter is more than 10 percent. |
• | The Engine Run Time parameter is more than 202 seconds. |
• | The Engine Speed parameter is between 1,100-2,500 RPM. |
• | The BARO Sensor parameter is more than 70 kPa. |
• | The Mass Airflow (MAF) Sensor parameter is between 20-40 g/s. |
• | The Loop Status parameter is Closed. |
• | The Throttle Position (TP) Indicated Angle parameter is more than 3 percent. |
• | These DTCs run once per drive cycle when the above conditions are met for 1 second. |
• | DTCs P0068, P0101, P0102, P0103, P0106, P0107, P0108, P0112, P0113, P0116, P0117, P0118, P0120, P0121, P0122, P0123, P0128, P0201, P0202, P0203, P0204, P0205, P0206, P0207, P0208, P0220, P0222, P0223, P0442, P0443, P0446, P0449, P0455, P0496, P1516, P2101, P2119, P2135, P2176 are not set. |
• | The Ignition 1 Signal parameter is between 10-18 volts. |
• | The engine run time is more than 101 seconds. |
• | These DTCs run continuously when the above conditions are met. |
• | DTCs P0068, P0101, P0102, P0103, P0106, P0107, P0108, P0112, P0113, P0116, P0117, P0118, P0120, P0121, P0122, P0123, P0128, P0201, P0202, P0203, P0204, P0205, P0206, P0207, P0208, P0220, P0222, P0223, P0442, P0443, P0446, P0449, P0455, P0496, P1516, P2101, P2119, P2135, P2176 are not set. |
• | The Ignition 1 Signal parameter is between 10-18 volts. |
• | The Engine Run Time parameter is more than 101 seconds. |
• | The Loop Status parameter is closed. |
• | These DTCs run once per drive cycle when the above conditions are met. |
• | DTCs P0068, P0101, P0102, P0103, P0106, P0107, P0108, P0112, P0113, P0116, P0117, P0118, P0120, P0121, P0122, P0123, P0128, P0201, P0202, P0203, P0204, P0205, P0206, P0207, P0208, P0220, P0222, P0223, P0442, P0443, P0446, P0449, P0455, P0496, P1516, P2101, P2119, P2135, P2176 are not set. |
• | The ECT Sensor parameter is more than 70°C (158°F). |
• | The Engine Speed parameter is between 1,100-2,500 RPM. |
• | The Ignition 1 Signal parameter is between 10-18 volts. |
• | The Engine Run Time parameter is more than 202 seconds. |
• | The Loop Status parameter is Closed. |
• | The TP Indicated Angle parameter is more than 5 percent. |
• | The Fuel Level Sensor parameter is more than 10 percent. |
• | The BARO parameter is more than 70 kPa. |
• | The MAF Sensor parameter is between 20-40 g/s. |
• | These DTCs run once per drive cycle when the above conditions are met for 1 second. |
• | The control module detects that the HO2S 1 rich-to-lean or lean-to-rich average response time is more than 0.14 second. |
• | These DTCs set within 60 seconds when the above condition is met. |
• | The control module detects that the HO2S 1 parameter is between 400-500 mV. |
• | The Throttle Position (TP) Indicated Angle parameter changes more than 5 percent. |
• | These DTCs set within 101 seconds when the above conditions are met. |
• | The control module detects that the HO2S 2 parameter is between 400-500 mV. |
• | The TP Indicated Angle parameter changes more than 5 percent 5 times. |
• | These DTCs set within 101 seconds when the above conditions are met. |
• | The control module detects that the HO2S 1 rich-to-lean counts, or the lean-to-rich counts are less than a calibrated value. |
• | These DTCs set within 60 seconds when the above condition is met. |
DTC P0133, P0134, P0140, P0153, P0154, P0160, P1133, P1153 are Type B DTCs.
DTC P0133, P0134, P0140, P0153, P0154, P0160, P1133, P1153 are Type B DTCs.
Powertrain Diagnostic Trouble Code (DTC) Type Definitions
• | If any HO2S heater DTCs are set, perform those diagnostics first. |
• | Allow the engine to reach operating temperature. |
• | Engine running, observe the affected HO2S parameter with a scan tool. |
- | The pre-catalyst oxygen sensors value should vary from below 200 mV to above 800 mV and respond to fueling changes. |
- | The post-catalyst oxygen sensors value should change more than 200 mV when the throttle is quickly cycled 3 times from closed to wide open and back to closed after running the engine at 1,500 RPM for 30 seconds. |
• | The affected HO2S may be damaged due to contamination. Prior to replacing the affected HO2S, inspect for the following sources of contamination: |
Notice: Refer to Silicon Contamination of Heated Oxygen Sensors Notice in the Preface section.
- | A silicon contaminated HO2S |
- | Fuel contamination--Refer to Alcohol/Contaminants-in-Fuel Diagnosis . |
- | Engine oil consumption--Refer to Oil Consumption Diagnosis . |
- | Engine coolant consumption--Refer to Loss of Coolant . |
Important: All modules must be powered down or misdiagnosis may result.
⇒ | If more than the specified range, test the appropriate HO2S low signal circuit for an open/high resistance. If the circuit tests normal, replace the ECM. |
⇒ | If more than the specified value, test the appropriate HO2S high signal circuit for a short to voltage. If the circuit tests normal, replace the ECM. |
⇒ | If less than the specified value, test the appropriate HO2S high signal circuit for a short to ground. If the circuit tests normal, replace the ECM. |
⇒ | If the appropriate scan tool HO2S parameter does not toggle correctly, test the HO2S high signal circuit for an open/high resistance. If the circuits test normal, replace the ECM. |
Notice: Refer to Heated Oxygen Sensor Resistance Learn Reset Notice in the Preface section.
Important: Always perform the Diagnostic Repair Verification after completing the diagnostic procedure.
• | Control Module References for ECM replacement, setup, and programming |