• | 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. |
Circuit | Short to Ground | High Resistance | Open | Short to Voltage | Signal Performance |
---|---|---|---|---|---|
HO2S High Signal | P0131, P0132, P0137, P0140, P1133, P2A00 | P0131, P0132, P0133, P0134, P0137, P013A, P013B, P013E, P013F, P0140, P1133, P2A00 | P0131, P0132, P0133, P0134, P0137, P013A, P013B, P013E, P013F, P0140, P1133, P2A00 | P0132, P0134, P0138, P0140, P1133, P2A00 | P0133, P0134, P013A, P013B, P013E, P013F, P0140, P1133, P2270, P2A00 |
HO2S Low Signal | P2A00 | P0131, P0132, P0133, P0134, P0138, P013A, P013B, P013E, P013F, P0140, P1133, P2A00 | P0131, P0132, P0133, P0134, P0138, P013A, P013B, P013E, P013F, P0140, P1133, P2A00 | P0134, P0138, P0140, P1133, P2A00 | P2271, P2A01 |
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 engine control module (ECM) supplies the HO2S with a reference, or bias, voltage of about 450 mV. When the engine is first started, the ECM 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, P0131, P0132, P0134, P0201, P0202, P0203, P0204, P0220, P0222, P0223, P0300, P0442, P0443, P0446, P0449, P0451, P0452, P0453, P0454, P0455, P0496, P1516, P2101, P2119, P2135, P2176 are not set. |
• | The HO2S 2 heater has been on for more than 40 seconds. |
• | The intake air temperature (IAT) is more than -40°C (-40°F). |
• | The purge duty cycle is equal to or greater than 0 percent. |
• | The fuel composition is less than 87 percent ethanol. |
• | The barometric pressure is greater than 70 kPa. |
• | Power enrichment is not active. |
• | Decel fuel cutoff (DFCO) is not active. |
• | 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 120 seconds. |
• | The Engine Speed parameter is between 1,000-3,500 RPM. |
• | The Mass Airflow (MAF) Sensor parameter is between 13-40 g/s. |
• | The Loop Status parameter is Closed. |
• | The Throttle Position (TP) Indicated Angle parameter is more than 4 percent. |
• | DTC P0133 runs once per drive cycle when the above conditions are met for 3 seconds. |
• | DTCs P0068, P0101, P0102, P0103, P0120, P0121, P0122, P0123, P0220, P0222, P0223, 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 200 seconds. |
• | The fuel composition is equal to or less than 87 percent ethanol. |
• | DTC P0134 runs continuously when the above conditions are met. |
• | DTCs P0068, P0101, P0102, P0103, P0106, P0107, P0108, P0112, P0113, P0116, P0117, P0118, P013B, P013E, P013F, P0120, P0121, P0122, P0123, P0128, P0171, P0172, P0201, P0202, P0203, P0204, P0220, P0222, P0223, P0300, P1174, P1516, P2101, P2119, P2135, P2176, P2270, P2271 are not set. |
• | The system voltage is between 10-18V. |
• | The fuel level is more than 10 percent. |
• | Engine run time is equal to or more than 40 seconds. |
• | DTCs P013E and P2270 has run and passed. |
THEN |
• | DFCO is active. |
• | APP is stable. |
• | TCC is locked. |
• | This DTC runs once per trip. |
• | DTCs P0068, P0101, P0102, P0103, P0106, P0107, P0108, P0112, P0113, P0116, P0117, P0118, P013A, P013E, P013F, P0120, P0121, P0122, P0123, P0128, P0171, P0172, P0201, P0202, P0203, P0204, P0220, P0222, P0223, P0300, P1174, P1516, P2101, P2119, P2135, P2176, P2270, P2271 are not set. |
• | The system voltage is between 10-18V. |
• | The fuel level is more than 10 percent. |
• | Engine run time is equal to or more than 40 seconds. |
• | DTC P013A, P013E, P013F, P2270, and P2271 have run and passed. |
• | This DTC runs once per trip. |
• | DTCs P0068, P0101, P0102, P0103, P0106, P0107, P0108, P0112, P0113, P0116, P0117, P0118, P013A, P013B, P013F, P0120, P0121, P0122, P0123, P0128, P0171, P0172, P0201, P0202, P0203, P0204, P0220, P0222, P0223, P0300, P1174, P1516, P2101, P2119, P2135, P2176, P2270, P2271 are not set. |
• | The system voltage is between 10-18V. |
• | The fuel level is more than 10 percent. |
• | DTC P2270 has run and passed. |
THEN |
• | DFCO is active. |
• | APP is stable. |
• | TCC is locked. |
• | This DTC runs once per trip. |
• | DTCs P0068, P0101, P0102, P0103, P0106, P0107, P0108, P0112, P0113, P0116, P0117, P0118, P013A, P013B, P013E, P0120, P0121, P0122, P0123, P0128, P0171, P0172, P0201, P0202, P0203, P0204, P0220, P0222, P0223, P0300, P1174, P1516, P2101, P2119, P2135, P2176, P2270, P2271 are not set. |
• | The system voltage is between 10-18V. |
• | The fuel level is more than 10 percent. |
• | DTC P013A, P013E, P2270, and P2271 have run and passed. |
THEN |
• | This DTC runs once per trip. |
• | DTCs P0068, P0101, P0102, P0103, P0120, P0121, P0122, P0123, P0220, P0222, P0223, P1516, P2101, P2119, P2135, P2176 are not set. |
• | The ECT Sensor parameter is more than 70°C (158°F). |
• | The Ignition 1 Signal parameter is between 10-18 volts. |
• | The Engine Run Time parameter is more than 200 seconds. |
• | The fuel composition is equal to or less than 87 percent ethanol. |
• | DTC P0140 runs 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, P0131, P0132, P0134, P0201, P0202, P0203, P0204, P0220, P0222, P0223, P0300, P0442, P0443, P0446, P0449, P0451, P0452, P0453, P0454, 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 1,000-3,500 RPM. |
• | The Ignition 1 Signal parameter is between 10-18 volts. |
• | The Engine Run Time parameter is more than 120 seconds. |
• | The Loop Status parameter is Closed. |
• | The TP Indicated Angle parameter is more than 4 percent. |
• | The Fuel Level Sensor parameter is more than 10 percent. |
• | The MAF Sensor parameter is between 13-40 g/s. |
• | The Intake Air Temperature parameter is more than -40°C (-40°F). |
• | The fuel composition is less than 87 percent ethanol. |
• | The BARO parameter is more than 70 kPa. |
• | Power enrichment is not active. |
• | Decel fuel cutoff (DFCO) is not active. |
• | DTC P1133 runs once per drive cycle when the above conditions are met for 3 seconds. |
• | DTCs P0068, P0101, P0102, P0103, P0106, P0107, P0108, P0112, P0113, P0116, P0117, P0118, P0120, P0121, P0122, P0123, P0128, P013A, P013B, P013E, P013F, P0171, P0172, P0201, P0202, P0203, P0204, P0220, P0222, P0223, P0300, P1174, P1516, P2101, P2119, P2135, P2176, P2270, P2271 are not set. |
• | The system voltage is between 10-18V. |
• | The fuel level is more than 10 percent. |
• | Engine run time is equal to or more than 40 seconds. |
• | The engine speed is between 1,250-1,950 RPM. |
• | Airflow is equal to or more than 3 g/s and equal to or less than 12 g/s. |
• | The vehicle speed is equal to or more than 54.7 km/h (34 mph) and equal to or less than 120 km/h (74.6 mph). |
• | The fuel state is in closed loop. |
• | The EVAP diagnostics are not in control of purge. |
• | The Ethanol Estimate is not in progress. |
• | The Post Cell Enabled. |
• | The Power Take-Off is not active. |
• | The EGR diagnostic is not intrusive. |
• | The Heater Warm-up Delay is more than 120 seconds. |
• | The catalytic converter temperature is equal to or more than 650°C (1,202°F), and equal to less than 900°C (1,652°F). |
• | This DTC runs once per trip when all of the above conditions have been met for 1 second. |
• | DTCs P0068, P0101, P0102, P0103, P0106, P0107, P0108, P0112, P0113, P0116, P0117, P0118, P0120, P0121, P0122, P0123, P0128, P013A, P013B, P013E, P013F, P0171, P0172, P0201, P0202, P0203, P0204, P0220, P0222, P0223, P0300, P1174, P1516, P2101, P2119, P2135, P2176, P2270 are not set. |
• | The system voltage is between 10-18V. |
• | The fuel level is more than 10 percent. |
• | The engine speed is 1,250-1,950 RPM. |
• | The engine airflow is 3-12 gps. |
• | The vehicle speed is 55-120 kph (34.2-74.6 mph). |
• | The predicted catalyst temperature is 650-900°C (1,202-1,652°F). |
• | Engine run time is equal to or more than 40 seconds. |
• | DTC P013A, P013E, and P2270 have run and passed. |
THEN |
• | DFCO is active. |
• | APP is stable. |
• | TCC is locked. |
• | This DTC runs once per trip. |
• | DTCs P0068, P0106, P0107, P0108, P0116, P0117, P0118, P0120, P0121, P0122, P0123, P0128, P0131, P0132, P0201, P0202, P0203, P0204, P0220, P0222, P0223, P1516, P2101, P2119, P2135, P2176 are not set. |
• | The Engine Run Time parameter is more than 100 seconds. |
• | Decel fuel cutoff (DFCO) is not active. |
• | The Engine speed parameter is between 500-3,400 RPM. |
• | The Ignition 1 Signal parameter is between 10-18 volts. |
• | The Mass Airflow (MAF) Sensor parameter is between 3.2-30 g/s. |
• | The ECT Sensor parameter is more than 70°C (158°F). |
• | DTC P2A00 runs continuously when the above conditions are met for 5 seconds. |
• | DTCs P0053, P0054, P0068, P0101, P0102, P0103, P0106, P0107, P0108, P0120, P0121, P0122, P0123, P0131, P0132, P0133, P0134, P0135, P0137, P0140, P0141, P0152, P0171, P0172, P0201, P0202, P0203, P0204, P0220, P0222, P0223, P0300, P0442, P0443, P0446, P0449, P0451, P0452, P0453, P0454, P0455, P0496, P1133, P1174, P1516, P2101, P2119, P2135, P2176 are not set. |
• | The system voltage is 10-18V. |
• | The fuel level is more than 10 percent. |
• | The engine speed is 1,000-3,500 RPM. |
• | The engine airflow is 5-50 gps |
• | The vehicle speed is 64-212 kph (40-132 mph). |
• | Closed Loop is active. |
• | DTC P2A01 runs once per ignition cycle when the above conditions are met for 5 seconds. |
• | The ECM detects that the HO2S 1 rich-to-lean or lean-to-rich average response time is more than 0.1 second. |
• | DTC P0133 sets within 60 seconds when the above condition is met. |
• | The ECM detects that the HO2S 1 parameter is between 400-500 mV for 100 seconds. |
• | The Throttle Position (TP) Indicated Angle parameter changes more than 1 percent, 3 times. |
• | DTC P0134 sets within 100 seconds when the above conditions are met. |
• | The ECM detects that the EWMA of the normalized integral value equals 8.4 integral units. |
OR |
• | The ECM detects that the accumulated mass air flow monitored during rich-to-lean transitions between 450-150 mV is more than 28 grams. |
• | The ECM detects that the EWMA of the normalized integral value equals 8.2 integral units. |
OR |
• | The ECM detects that the accumulated mass air flow monitored during lean-to-rich transitions between 300-600 mV is more than 130 grams. |
The ECM detects that the O2 sensor cannot achieve voltage below 450 mV within 28 grams of accumulated air flow.
The ECM detects that the O2 sensor cannot achieve voltage above 300 mV within 130 grams of accumulated air flow.
• | The ECM detects that the HO2S 2 parameter is between 400-500 mV. |
• | The TP Indicated Angle parameter changes more than 1 percent 3 times. |
• | DTC P0140 sets within 100 seconds when the above conditions are met. |
• | The ECM detects that the HO2S 1 rich-to-lean counts, or the lean-to-rich counts are less than a calibrated value. |
• | DTC P1133 sets within 60 seconds when the above condition is met. |
• | The ECM detects that the O2 sensor cannot achieve voltage equal to or more than 775 mV. |
AND |
• | The ECM detects that the accumulated mass air flow monitored during the Stuck Lean Voltage Test is more than 55 grams. |
• | The ECM detects that the O2 sensor cannot achieve voltage equal to or less than 100 mV. |
AND |
• | The ECM detects that the accumulated mass air flow monitored during the Stuck Rich Voltage Test is more than 40 grams. |
• | The ECM detects that the Loop Status parameter is open. |
• | DTC P2A00 sets within 50 seconds when the above condition is met. |
• | The ECM detects that the HO2S 2 is stuck in a normal voltage range. |
• | DTC P2A01 sets within 50 seconds when the above condition is met. |
• | DTCs P0133, P0134, P013E, P013F, P0140, P1133, P2270, P2271, P2A00 are Type B DTCs. |
• | DTCs P013A and P013B are Type A DTCs. |
• | DTCs P0133, P0134, P013E, P013F, P0140, P1133, P2270, P2271, P2A00 are Type B DTCs. |
• | DTCs P013A and P013B are Type A DTCs. |
Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Control Module References for scan tool information
• | 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. |
Caution: Refer to Silicon Contamination of Heated Oxygen Sensors Caution 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 Cooling System Leak Testing. |
Note: 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 terminal B 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 terminal B 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. |
Caution: Refer to Heated Oxygen Sensor Resistance Learn Reset Caution in the Preface section.
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
• | Control Module References for ECM replacement, setup, and programming |