Engine Controls - 2.2l (DTC p0030 to p0136) Chevrolet Cobalt I

Circuit Description

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. A heating element inside the HO2S minimizes the time required for the sensor to reach operating temperature. Voltage is provided to the heater by the ignition 1 voltage circuit through a fuse. With the engine running, ground is provided to the heater by the HO2S heater low control circuit, through a low side driver within the engine control module (ECM).

The ECM commands the heater ON or OFF to maintain a specific HO2S operating temperature range. The ECM monitors the voltage on the HO2S heater low control circuit for heater fault diagnosis. If the ECM detects that the HO2S heater low control circuit voltage is not within a specified range, DTC P0030 sets for HO2S 1, or DTC P0036 sets for HO2S 2.

DTC Descriptors

This diagnostic procedure supports the following DTCs

1. DTC P0030 O2S Heater Control Circuit Bank 1 Sensor 1
2. DTC P0036 O2S Heater Control Circuit Bank 1 Sensor 2

Conditions for Running the DTC

1. The Ignition 1 Signal parameter is between 11-18 volts.
2. The engine speed is more than 425 RPM.
3. DTC P0030 or P0036 runs continuously when the above conditions are met.

Conditions for Setting the DTC

1. The ECM detects that the affected HO2S heater low control circuit is not within a specified range.
2. DTC P0030 or P0036 sets within 3 seconds when the above condition is met.

Action Taken When the DTC Sets

1. The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
2. 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

1. The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
2. A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
3. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
4. Clear the MIL and the DTC with a scan tool.

DTC P0030 or P0036

The engine control module (ECM) uses the following information to calculate an expected airflow rate

1. The throttle position (TP)
2. The barometric pressure (BARO)
3. The intake air temperature (IAT)
4. The engine RPM

If the ECM detects the airflow rate is more than expected, DTC P0068 sets.

DTC Descriptor

This diagnostic procedure supports the following DTC

DTC P0068 Throttle Body Airflow Performance

1. DTCs P0641, P0651, P1516, P2101, P2119, P2176 are not set.
2. The engine is running and the engine speed is more than 600 RPM.
3. DTC P0068 runs continuously when the above conditions are met.

1. The ECM detects that the calculated airflow rate is more than expected.
2. The above condition is present for more than 0.2 second.

1. The control module illuminates the malfunction indicator lamp (MIL) when the diagnostic runs and fails.
2. The control module records the operating conditions at the time the diagnostic fails. The control module stores this information in the Freeze Frame and/or the Failure Records.
3. The control module commands the TAC system to operate in the Reduced Engine Power mode.
4. A message center or an indicator displays Reduced Engine Power.
5. Under certain conditions the control module commands the engine OFF.

1. The PCM will turn OFF the malfunction indicator lamp (MIL) during the third consecutive trip in which the diagnostic has run and passed.
2. The history DTC will clear after 40 consecutive warm-up cycles have occurred without a malfunction.
3. The DTC can be cleared by using a scan tool.

Diagnostic Aids

1. Inspect for the following conditions: The throttle blade for damage A skewed cam sensor signal-Inspect for signals that are intermittently shorted to ground, causing a fluctuating RPM on the scan tool.
2. If the condition is intermittent, refer to «Intermittent Conditions»(/chevrolet/cobalt/i-2004-2010/remont/testing-diagnostics/#engine-controls-22l-troubleshooting-diagnosis__intermittent-conditions) .

Test Description

The numbers below refer to the step numbers on the diagnostic table.

1. 5: This step will determine if the manifold absolute pressure (MAP) sensor voltage is within the proper range at idle.
2. 6: This step will determine if the MAP sensor responds properly to the change in manifold pressure.
3. 7: A throttle blade that sticks or binds may set this code. Opening the throttle through the entire range will indicate conditions such as these.
4. 9: When the ECM detects a condition within the ETC system, other DTCs may set due to the many redundant tests run continuously on this system. Locating and repairing one individual condition may correct more than one DTC. Keep this in mind when reviewing captured DTC info.

DTC P0068

The intake flow rationality diagnostic provides the within-range rationality check for the mass air flow (MAF), manifold absolute pressure (MAP), and the throttle position (TP) sensors. This is an explicit model-based diagnostic containing 4 separate models for the intake system.

1. The throttle model describes the flow through the throttle body and is used to estimate the MAF through the throttle body as a function of barometric pressure (BARO), TP, intake air temperature (IAT), and estimated MAP.
2. The first intake manifold model describes the intake manifold and is used to estimate MAP as a function of the MAF into the manifold from the throttle body and the MAF out of the manifold caused by engine pumping. The flow into the manifold from the throttle uses the MAF estimate calculated from the above throttle model.
3. The second intake manifold model is identical to the first intake manifold model except that the MAF sensor measurement is used instead of the throttle model estimate for the throttle air input.
4. A fourth model is created from the combination and additional calculations of the throttle model and the first intake manifold model.

The estimates of MAF and MAP obtained from this system of models and calculations are then compared to the actual measured values from the MAF, MAP, and the TP sensors and to each other to determine the appropriate DTC to fail. The following table illustrates the possible failure combinations and the resulting DTC or DTCs.

DTC P0101

If the engine control module (ECM) detects that the actual measured airflow from MAF, MAP, and TP is not within range of the calculated airflow that is derived from the system of models DTC P0101 sets.

This diagnostic procedure supports the following DTC

DTC P0101 Mass Air Flow (MAF) System Performance

1. DTCs P0102, P0103, P0112, P0113, P0107, P0108, P0117, P0118, P0335, P0336 are not set.
2. The engine speed is between 400-6,400 RPM.
3. The IAT Sensor parameter is between -7 and +125°C (+19 and +257°F).
4. The ECT Sensor parameter is between 70-125°C (158-257°F).
5. This DTC runs continuously within the enabling conditions.

The ECM detects that the actual measured airflow from MAF, MAP, and TP is not within range of the calculated airflow that is derived from the system of models for more than 0.5 second.

1. The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
2. 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.

1. The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
2. A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
3. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
4. Clear the MIL and the DTC with a scan tool.

1. Inspect the harness of the MAF sensor to verify that it is not routed too close to the following components: Any aftermarket accessories-Refer to «Checking Aftermarket Accessories»(/chevrolet/cobalt/i-2004-2010/remont/electrical-component-locations/#wiring-systems-electrical-power-management__checking-aftermarket-accessories) . Any solenoids Any relays Any motors
2. A wide open throttle acceleration from a stop should cause the MAF sensor parameter on the scan tool to increase rapidly. This increase should be from 3-6 g/s at idle to 120 g/s or more at the time of the 1-2 shift. If the increase is not observed, inspect for a restriction in the induction system or the exhaust system.
3. A skewed or stuck engine coolant temperature (ECT) or IAT sensor will cause the calculated models to be inaccurate and may cause this DTC to run when it shouldn't.
4. A steady or intermittent high resistance of 15 ohms or more on the ignition 1 voltage circuit will cause the MAF sensor values to be skewed high by up to 60 g/s, and may cause this DTC to set. A high resistance will cause a driveability concern before this DTC sets.
5. The BARO that is used by the ECM to calculate the air flow models is initially based on the MAP sensor at key ON. When the engine is running, the ECM will continually update the BARO value near wide open throttle using the MAP sensor and a calculation. A skewed MAP sensor will cause the calculated mass air flow value to be inaccurate and may result in a no start condition. With the ignition ON and the engine OFF, the MAP Sensor parameter varies with the altitude. 101 kPa is the approximate value near sea level. This value will decrease by approximately 3 kPa for every 305 meters (1,000 feet) of altitude.
6. A high resistance on the low reference circuit of the MAP sensor will skew the sensor value and may cause this DTC to set.
7. If the condition is intermittent, refer to «Inducing Intermittent Fault Conditions»(/chevrolet/cobalt/i-2004-2010/remont/electrical-component-locations/#wiring-systems-electrical-power-management) and «Intermittent Conditions»(/chevrolet/cobalt/i-2004-2010/remont/testing-diagnostics/#engine-controls-22l-troubleshooting-diagnosis__intermittent-conditions) .

The numbers below refer to the step numbers on the diagnostic table.

1. 5: This step will determine if any mechanical faults have caused this DTC to set.
2. 12: This voltage drop test will determine if high resistance has caused this DTC to set.
3. 14: This step verifies the voltage signal from the ECM to the MAF sensor connector.
4. 15: This step will determine if the ECM can accurately process the frequency signal that it receives from the MAF sensor.
5. 16: This step will determine if an abnormal resistance of less than 1,150 ohms has skewed the MAF sensor frequency signal.

DTC P0101

The mass air flow (MAF) sensor is an air flow meter that measures the amount of air entering the engine. The engine control module (ECM) uses the MAF sensor signal to provide the correct fuel delivery for all engine speeds and loads. A small quantity of air entering the engine indicates a deceleration or idle condition. A large quantity of air entering the engine indicates an acceleration or high load condition. The MAF sensor has the following circuits

1. An ignition 1 voltage circuit
2. A ground circuit
3. A signal circuit

The ECM applies a voltage to the sensor on the signal circuit. The sensor uses the voltage to produce a frequency based on the inlet air flow through the sensor bore. The frequency varies within a range of near 2,500 Hertz at idle to near 10,000 Hertz at maximum engine load. If the ECM detects the frequency signal is less than the possible range of a correctly operating MAF sensor DTC P0102 sets.

This diagnostic procedure supports the following DTC

DTC P0102 Mass Air Flow (MAF) Sensor Circuit Low Frequency

1. The engine is running for more than 30 seconds.
2. The engine speed is more than 500 RPM.
3. The ignition 1 signal is more than 11 volts.
4. The above conditions are met for more than 2.5 seconds.
5. This DTC runs continuously within the enabling conditions.

The ECM detects that the MAF sensor frequency signal is less than 100 Hertz for more than 3 seconds.

1. The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
2. 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.

1. The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
2. A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
3. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
4. Clear the MIL and the DTC with a scan tool.

1. Inspect for any contamination or debris on the sensing elements of the MAF sensor.
2. A wide open throttle (WOT) acceleration from a stop should cause the MAF sensor parameter on the scan tool to increase rapidly. This increase should be from 3-6 g/s at idle to 120 g/s or more at the time of the 1-2 shift. If the increase is not observed, inspect for a restriction in the induction system or the exhaust system.
3. A high resistance of 15 ohms or more on the ground circuit or the ignition 1 circuit of the MAF sensor may cause this DTC to set. A high resistance will cause a driveability concern before this DTC sets.
4. If the condition is intermittent, refer to «Intermittent Conditions»(/chevrolet/cobalt/i-2004-2010/remont/testing-diagnostics/#engine-controls-22l-troubleshooting-diagnosis__intermittent-conditions) and «Inducing Intermittent Fault Conditions»(/chevrolet/cobalt/i-2004-2010/remont/electrical-component-locations/#wiring-systems-electrical-power-management) .

The numbers below refer to the step numbers on the diagnostic table.

1. 5: This step will determine if any mechanical faults have caused this DTC to set.
2. 7: This voltage drop test will determine if high resistance has caused this DTC to set.
3. 9: This step verifies the voltage signal from the ECM to the MAF sensor connector.
4. 10: This step tests the signal circuit of the MAF sensor for a short to another 5-volt reference circuit.
5. 11: This step will determine if the ECM is able to process the frequency signal that it receives from the MAF sensor.
6. 14: This step will determine which portion of the circuit or which component is shorted to ground.
7. 17: This step verifies that the signal circuit is not shorted to any other ECM circuit.

DTC P0102

The mass air flow (MAF) sensor is an air flow meter that measures the amount of air entering the engine. The engine control module (ECM) uses the MAF sensor signal to provide the correct fuel delivery for all engine speeds and loads. A small quantity of air entering the engine indicates a deceleration or idle condition. A large quantity of air entering the engine indicates an acceleration or high load condition. The MAF sensor has the following circuits

1. An ignition 1 voltage circuit
2. A ground circuit
3. A signal circuit

The ECM applies a voltage to the sensor on the signal circuit. The sensor uses the voltage to produce a frequency based on the inlet air flow through the sensor bore. The frequency varies within a range of near 2,500 Hertz at idle to near 10,000 Hertz at maximum engine load. If the ECM detects a frequency signal that is more than the possible range of a correctly operating MAF sensor DTC P0103 sets.

This diagnostic procedure supports the following DTC

DTC P0103 Mass Air Flow (MAF) Sensor Circuit High Frequency

1. The engine is running for more than 30 seconds.
2. The engine speed is more than 500 RPM.
3. The ignition 1 signal is more than 11 volts.
4. The above conditions are met for more than 2.5 seconds.
5. This DTC runs continuously within the enabling conditions.

The ECM detects that the MAF sensor frequency signal is more than 11,000 Hertz for more than 3 seconds.

1. The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
2. 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.

1. The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
2. A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
3. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
4. Clear the MIL and the DTC with a scan tool.

1. Inspect the Air Induction System for any water intrusion. The water rapidly cools the hot sensing elements in the sensor causing a false indication of excessive air flow. Any water that reaches the MAF sensor will skew the sensor and may cause this DTC to set.
2. A poor connection at the fuse for the ignition 1 voltage circuit of the MAF sensor may cause this DTC to set.
3. If the condition is intermittent, refer to «Intermittent Conditions»(/chevrolet/cobalt/i-2004-2010/remont/testing-diagnostics/#engine-controls-22l-troubleshooting-diagnosis__intermittent-conditions) and «Inducing Intermittent Fault Conditions»(/chevrolet/cobalt/i-2004-2010/remont/electrical-component-locations/#wiring-systems-electrical-power-management) .

The numbers below refer to the step numbers on the diagnostic table.

1. 3: This step tests for electromagnetic interference (EMI) on the signal circuit of the MAF sensor. A frequency reading with the MAF sensor disconnected may indicate an EMI related fault or a poor connection at the ECM. Disconnecting the MAF sensor may set additional related DTCs.
2. 4: This step will determine if incorrect harness routing has caused this DTC to set.
3. 5: This step will determine if water intrusion has caused this DTC to set.
4. 6: This step will determine if high resistance at any point in the ignition 1 voltage circuit has caused this DTC to set.

DTC P0103

The manifold absolute pressure (MAP) sensor measures the pressure inside the intake manifold. Pressure in the intake manifold is affected by engine speed, throttle opening, air temperature, and barometric pressure (BARO). A diaphragm within the MAP sensor is displaced by the pressure changes that occur from the varying load and operating conditions of the engine. The sensor translates this action into electrical resistance. The MAP sensor wiring includes three circuits. The engine control module (ECM) supplies a regulated 5 volts to the sensor on a 5-volt reference circuit. The ECM supplies a ground on a low reference circuit. The MAP sensor provides a signal voltage to the ECM, relative to the pressure changes on the MAP sensor signal circuit. The ECM converts the signal voltage input to a pressure value.

Under normal operation, the highest pressure that can exist in the intake manifold is equal to the BARO. This occurs when the vehicle is operated at wide open throttle (WOT), or when the ignition is ON while the engine is OFF. Under these conditions, the ECM uses the MAP sensor to determine the current BARO. The lowest manifold pressures occur when the vehicle is idling or decelerating. The MAP can range from 10 kPa when pressures are low to as much as 104 kPa when pressures are high, depending on the BARO.

Within the ECM, the intake flow rationality diagnostic has the ability to determine an inaccurate input from the three systems it monitors. Calibrated within the diagnostic are estimates for the MAP, the mass air flow (MAF), and the throttle position (TP) for all engine operating conditions. The diagnostic compares the estimated values to the actual sensor inputs. If the ECM detects that the MAP sensor input is not within a calibrated limit of the estimated value, DTC P0106 sets.

This diagnostic procedure supports the following DTC

DTC P0106 Manifold Absolute Pressure (MAP) Sensor Performance

1. DTCs P0102, P0103, P0107, P0108, P0112, P0113, P0117, P0118, P0335, P0336 are not set.
2. The engine speed is between 400-6,400 RPM.
3. The engine coolant temperature (ECT) is between 70-125°C (158-257°F).
4. The intake air temperature (IAT) is between -7 to +125°C (+19 to +257°F).
5. This DTC runs continuously within the enabling conditions.

The ECM detects that the MAP sensor pressure is not within the calibrated limit of the estimated value for more than 1 second.

1. The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
2. 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.

1. The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
2. A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
3. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
4. Clear the MIL and the DTC with a scan tool.

The numbers below refer to the step numbers on the diagnostic table.

1. 4: This step tests the ability of the MAP sensor to correctly indicate BARO.
2. 12: The measurement noted in this step will be used in subsequent steps if the measurement does not exceed the specified value.
3. 14: This step calculates the resistance in the 5-volt reference circuit.
4. 15: This step calculates the resistance in the low reference circuit.

DTC P0106

The manifold absolute pressure (MAP) sensor measures the pressure inside the intake manifold. Pressure in the intake manifold is affected by engine speed, throttle opening, air temperature, and barometric pressure (BARO). A diaphragm within the MAP sensor is displaced by the pressure changes that occur from the varying load and operating conditions of the engine. The sensor translates this action into electrical resistance. The MAP sensor wiring includes 3 circuits. The engine control module (ECM) supplies a regulated 5 volts to the sensor on a 5-volt reference circuit. The ECM supplies a ground on a low reference circuit. The MAP sensor provides a signal voltage to the ECM, relative to the pressure changes, on the MAP sensor signal circuit. The ECM converts the signal voltage input to a pressure value.

Under normal operation the highest pressure that can exist in the intake manifold is equal to BARO. This occurs when the vehicle is operated at wide-open throttle (WOT) or when the ignition is on while the engine is off. Under these conditions, the ECM uses the MAP sensor to determine the current BARO. The lowest manifold pressures occur when the vehicle is idling or decelerating. MAP can range from 10 kPa, when pressures are low, to as much as 104 kPa when pressures are high, depending on the BARO. The ECM monitors the MAP sensor signal for pressure outside of the normal range. If the ECM detects that the MAP sensor pressure is excessively low, DTC P0107 sets.

This diagnostic procedure supports the following DTC

DTC P0107 Manifold Absolute Pressure (MAP) Sensor Circuit Low Voltage

1. The ignition is ON.
2. DTCs P0641, P0651, P1516, P1680, P1681, P2101, P2120, P2125, P2135, P2138, P2176 are not set.
3. The throttle angle is more than 0 percent when engine speed is less than 1,100 RPM. OR
4. The throttle angle is more than 5 percent when engine speed is more than 1,100 RPM.
5. This DTC runs continuously within the enabling conditions.

The ECM detects that the MAP sensor pressure is less than 12 kPa for more than 2 seconds.

1. The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
2. 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.

1. The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
2. A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
3. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
4. Clear the MIL and the DTC with a scan tool.

DTC P0107

The manifold absolute pressure (MAP) sensor measures the pressure inside the intake manifold. Pressure in the intake manifold is affected by engine speed, throttle opening, air temperature, and barometric pressure (BARO). A diaphragm within the MAP sensor is displaced by the pressure changes that occur from the varying load and operating conditions of the engine. The sensor translates this action into electrical resistance. The MAP sensor wiring includes 3 circuits. The engine control module (ECM) supplies a regulated 5 volts to the sensor on a 5-volt reference circuit. The ECM supplies a ground on a low reference circuit. The MAP sensor provides a signal voltage to the ECM, relative to the pressure changes, on the MAP sensor signal circuit. The ECM converts the signal voltage input to a pressure value.

Under normal operation the highest pressure that can exist in the intake manifold is equal to BARO. This occurs when the vehicle is operated at wide-open throttle (WOT) or when the ignition is on while the engine is off. Under these conditions, the ECM uses the MAP sensor to determine the current BARO. The lowest manifold pressures occur when the vehicle is idling or decelerating. MAP can range from 10 kPa, when pressures are low, to as much as 104 kPa when pressures are high, depending on the BARO. The ECM monitors the MAP sensor signal for pressure outside of the normal range. If the ECM detects that the MAP sensor pressure is excessively high, DTC P0108 sets.

This diagnostic procedure supports the following DTC

DTC P0108 Manifold Absolute Pressure (MAP) Sensor Circuit High Voltage

1. DTCs P0641, P0651, P1516, P1680, P1681, P2101, P2120, P2125, P2135, P2138, P2176 are not set.
2. The engine has been running for a period of time that is determined by the start-up coolant temperature. The time ranges from 8 seconds at less than -30°C (-22°F) to 3 seconds at more than 30°C (86°F).
3. The throttle angle is less than 2.2 percent when the engine speed is less than 1,100 RPM. OR
4. The throttle angle is less than 4.5 percent when the engine speed is more than 1,100 RPM.
5. This DTC runs continuously within the enabling conditions.

The ECM detects that the MAP sensor pressure is more than 102 kPa for more than 2 seconds.

1. The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
2. 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.

1. The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
2. A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
3. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
4. Clear the MIL and the DTC with a scan tool.

The number below refers to the step number on the diagnostic table.

1. 8: This step tests the ground path, from the sensor through the controller, for an open or excessive resistance.

DTC P0108

The intake air temperature (IAT) sensor is a variable resistor. The IAT sensor has a signal circuit and a low reference circuit. The IAT sensor measures the temperature of the air entering the engine. The engine control module (ECM) supplies 5 volts to the IAT signal circuit and a ground for the IAT low reference circuit. When the IAT sensor is cold, the sensor resistance is high. When the air temperature increases, the sensor resistance decreases. With high sensor resistance, the ECM detects a high voltage on the IAT signal circuit. With lower sensor resistance, the ECM detects a lower voltage on the IAT signal circuit. If the ECM detects an excessively low IAT signal voltage, indicating a high temperature, DTC P0112 sets.

This diagnostic procedure supports the following DTC

DTC P0112 Intake Air Temperature (IAT) Sensor Circuit Low Voltage

1. DTCs P0117, P0118, P0502, P0503 are not set.
2. The engine run time is more than 10 seconds.
3. The vehicle speed sensor (VSS) indicates that vehicle speed is more than 40 km/h (25 mph).
4. The engine coolant temperature (ECT) is less than 110°C (230°F).
5. This DTC runs continuously within the enabling conditions.

The ECM detects that the IAT sensor parameter is more than 149°C (300°F) for more than 5 seconds.

1. The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
2. 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.

1. The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
2. A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
3. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
4. Clear the MIL and the DTC with a scan tool.

DTC P0112

The intake air temperature (IAT) sensor is a variable resistor. The IAT sensor has a signal circuit and a low reference circuit. The IAT sensor measures the temperature of the air entering the engine. The engine control module (ECM) supplies 5 volts to the IAT signal circuit and a ground for the IAT low reference circuit. When the IAT sensor is cold, the sensor resistance is high. When the air temperature increases, the sensor resistance decreases. With high sensor resistance, the ECM detects a high voltage on the IAT signal circuit. With lower sensor resistance, the ECM detects a lower voltage on the IAT signal circuit. If the ECM detects an excessively high IAT signal voltage, indicating a low temperature, DTC P0113 sets.

This diagnostic procedure supports the following DTC

DTC P0113 Intake Air Temperature (IAT) Sensor Circuit High Voltage

1. DTCs P0101, P0102, P0103, P0117, P0118, P0502, P0503 are not set.
2. The engine run time is more than 10 seconds.
3. The vehicle speed sensor (VSS) indicates that vehicle speed is less than 1.6 km/h (1 mph).
4. The engine coolant temperature (ECT) is more than 50°C (122°F).
5. The mass air flow (MAF) is less than 12 g/s.
6. This DTC runs continuously within the enabling conditions.

The ECM detects that the IAT sensor parameter is less than -39°C (-38°F) for more than 5 seconds.

1. The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
2. 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.

1. The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
2. A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
3. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
4. Clear the MIL and the DTC with a scan tool.

The number below refers to the step number on the diagnostic table.

1. 6: This step tests for the proper operation of the circuit in the low voltage range.

DTC P0113

The engine coolant temperature (ECT) sensor is a variable resistor that measures the temperature of the engine coolant. The engine control module (ECM) supplies 5 volts to the ECT signal circuit and a ground for the ECT low reference circuit. When the ECT is cold, the sensor resistance is high. When the ECT increases, the sensor resistance decreases. With high sensor resistance, the ECM detects a high voltage on the ECT signal circuit. With lower sensor resistance, the ECM detects a lower voltage on the ECT signal circuit. If the ECM detects an excessively low ECT signal voltage, which is a high temperature indication, DTC P0117 sets.

This diagnostic procedure supports the following DTC

DTC P0117 Engine Coolant Temperature (ECT) Sensor Circuit Low Voltage

1. The engine is running for more than 10 seconds. OR
2. The engine run time is less than 10 seconds when the intake air temperature (IAT) is less than 70°C (158°F).
3. This DTC runs continuously within the enabling conditions.

The ECM detects that the ECT sensor parameter is more than 149°C (300°F) for more than 5 seconds.

1. The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
2. 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.

1. The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
2. A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
3. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
4. Clear the MIL and the DTC with a scan tool.

DTC P0117

The engine coolant temperature (ECT) sensor is a variable resistor, that measures the temperature of the engine coolant. The ECT sensor has a signal circuit and a low reference circuit. The engine control module (ECM) supplies 5 volts to the ECT signal circuit and a ground for the ECT low reference circuit. When the ECT is cold, the sensor resistance is high. When the ECT increases, the sensor resistance decreases. With high sensor resistance, the ECM detects a high voltage on the ECT signal circuit. With lower sensor resistance, the ECM detects a lower voltage on the ECT signal circuit. If the ECM detects an excessively high ECT signal voltage, which is a low temperature indication, DTC P0118 sets.

This diagnostic procedure supports the following DTC

DTC P0118 Engine Coolant Temperature (ECT) Sensor Circuit High Voltage

1. The engine is running for more than 1 minute. OR
2. The engine run time is less than 1 minute when the intake air temperature (IAT) is more than -7°C (19°F).
3. This DTC runs continuously within the enabling conditions.

The ECM detects that the ECT sensor parameter is less than -39°C (-38°F) for more than 5 seconds.

1. The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
2. 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.

1. The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
2. A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
3. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
4. Clear the MIL and the DTC with a scan tool.

DTC P0118

The throttle position (TP) sensors 1 and 2 are located within the throttle body assembly. Each sensor has the following components

1. A 5-volt reference circuit
2. A low reference circuit
3. A signal circuit

This provides the engine control module (ECM) with a signal voltage proportional to throttle plate movement. TP sensor 1 signal voltage at closed throttle is near the 5-volt reference and decreases as the throttle plate is opened. TP sensor 2 signal voltage at closed throttle is near the low reference and increases as the throttle plate is opened. If the ECM detects the TP sensor 1 signal voltage is not within the predicted range, DTC P0120 sets.

This diagnostic procedure supports the following DTC

DTC P0120 Throttle Position (TP) Sensor 1 Circuit

1. The ignition switch is in the Crank or Run position.
2. DTC P0641 is not set.
3. The ignition voltage is greater than 5.23 volts.
4. DTC P0120 runs continuously when the above conditions are met.

The ECM detects that the TP sensor 1 voltage is less than 0.27 volt or more than 4.67 volts for more than 0.4 second.

1. The control module illuminates the malfunction indicator lamp (MIL) when the diagnostic runs and fails.
2. The control module records the operating conditions at the time the diagnostic fails. The control module stores this information in the Freeze Frame and/or the Failure Records.
3. The control module commands the TAC system to operate in the Reduced Engine Power mode.
4. A message center or an indicator displays Reduced Engine Power.
5. Under certain conditions the control module commands the engine OFF.

1. The ECM will turn OFF the malfunction indicator lamp (MIL) during the third consecutive trip in which the diagnostic runs and passes.
2. The history DTC will clear after 40 consecutive warm-up cycles have occurred without a malfunction.
3. The DTC can be cleared by using a scan tool.

DTC P0120

The engine control module (ECM) uses the following information to calculate an expected airflow rate

1. The throttle position (TP)
2. The barometric pressure (BARO)
3. The manifold absolute pressure (MAP)
4. The intake air temperature (IAT)
5. The mass air flow (MAF)
6. The engine RPM

If the ECM detects the airflow rate is more than expected, DTC P0121 sets.

This diagnostic procedure supports the following DTC

DTC P0121 Throttle Position (TP) Sensor 1 Performance

1. DTCs P0641, P0651, P1516, P2101, P2119, P2176 are not set.
2. The engine is running and the engine speed is more than 600 RPM.

The ECM detects that the calculated airflow rate is more than expected.

1. The control module illuminates the malfunction indicator lamp (MIL) when the diagnostic runs and fails.
2. The control module records the operating conditions at the time the diagnostic fails. The control module stores this information in the Freeze Frame and/or the Failure Records.
3. The control module commands the TAC system to operate in the Reduced Engine Power mode.
4. A message center or an indicator displays Reduced Engine Power.
5. Under certain conditions the control module commands the engine OFF.

1. The PCM will turn OFF the malfunction indicator lamp (MIL) during the third consecutive trip in which the diagnostic has run and passed.
2. The history DTC will clear after 40 consecutive warm-up cycles have occurred without a malfunction.
3. The DTC can be cleared by using a scan tool.

The numbers below refer to the step numbers on the diagnostic table.

1. 5: This step will determine if the MAP sensor voltage is within the proper range at idle.
2. 6: This step will determine if the MAP sensor responds properly to the change in manifold pressure.
3. 9: When the ECM detects a condition within the ETC system, other DTCs may set due to the many redundant tests run continuously on this system. Locating and repairing one individual condition may correct more than one DTC. Keep this in mind when reviewing captured DTC info.

DTC P0121

The throttle position (TP) sensors 1 and 2 are located within the throttle body assembly. Each sensor has the following circuits

1. A 5-volt reference circuit
2. A low reference circuit
3. A signal circuit

This provides the engine control module (ECM) with a signal voltage proportional to the throttle plate movement. The TP sensor 1 signal voltage at closed throttle is near the 5-volt reference circuit and decreases as the throttle plate is opened. The TP sensor 2 signal voltage at closed throttle is near the low reference circuit and increases as the throttle plate is opened. If the ECM detects that the TP sensor 1 signal voltage is less than the predicted range, DTC P0122 sets.

This diagnostic procedure supports the following DTC

DTC P0122 Throttle Position (TP) Sensor 1 Circuit Low Voltage

1. The ignition switch is in the Crank or Run position.
2. DTC P0641 is not set.
3. The ignition voltage is greater than 5.23 volts.
4. DTC P0122 runs continuously when the above conditions are met.

The ECM detects that the TP sensor 1 voltage is less than 0.15 volt for more than 0.4 second.

1. The control module illuminates the malfunction indicator lamp (MIL) when the diagnostic runs and fails.
2. The control module records the operating conditions at the time the diagnostic fails. The control module stores this information in the Freeze Frame and/or the Failure Records.
3. The control module commands the TAC system to operate in the Reduced Engine Power mode.
4. A message center or an indicator displays Reduced Engine Power.
5. Under certain conditions the control module commands the engine OFF.

1. The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
2. A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
3. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
4. Clear the MIL and the DTC with a scan tool.

DTC P0122

The throttle position (TP) sensors 1 and 2 are located within the throttle body assembly. Each sensor has the following circuits

1. A 5-volt reference circuit
2. A low reference circuit
3. A signal circuit

This provides the engine control module (ECM) with a signal voltage proportional to the throttle plate movement. The TP sensor 1 signal voltage at closed throttle is near the 5-volt reference circuit and decreases as the throttle plate is opened. The TP sensor 2 signal voltage at closed throttle is near the low reference circuit and increases as the throttle plate is opened. If the ECM detects that the TP sensor 1 signal voltage is more than the predicted range, DTC P0123 sets.

This diagnostic procedure supports the following DTC

DTC P0123 Throttle Position (TP) Sensor 1 Circuit High Voltage

1. The ignition switch is in the Crank or Run position.
2. DTC P0641 is not set.
3. The ignition voltage is greater than 5.23 volts.
4. DTC P0123 runs continuously when the above conditions are met.

The ECM detects that the TP sensor 1 voltage is more than 4.75 volts for more than 0.4 second.

1. The control module illuminates the malfunction indicator lamp (MIL) when the diagnostic runs and fails.
2. The control module records the operating conditions at the time the diagnostic fails. The control module stores this information in the Freeze Frame and/or the Failure Records.
3. The control module commands the TAC system to operate in the Reduced Engine Power mode.
4. A message center or an indicator displays Reduced Engine Power.
5. Under certain conditions the control module commands the engine OFF.

1. The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
2. A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
3. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
4. Clear the MIL and the DTC with a scan tool.

DTC P0123

An engine coolant temperature (ECT) sensor monitors the temperature of the coolant. This input is used by the engine control module (ECM) for engine control and as an enabling criteria for some diagnostics.

The air flow into the engine is accumulated and used to determine if the vehicle has been driven within the conditions that would allow the engine coolant to heat up normally to the Closed Loop temperature. If the coolant temperature does not increase normally or does not reach the Closed Loop temperature, the diagnostics that use engine coolant temperature as enabling criteria may not run when expected.

This DTC will only run once per ignition cycle within the enabling conditions.

If the ECM detects the calibrated amount of air flow, vehicle speed and distance, and engine run time have been met, and the engine coolant has not met the Closed Loop temperature, DTC P0125 sets.

This diagnostic procedure supports the following DTC

DTC P0125 Engine Coolant Temperature (ECT) Insufficient For Closed Loop Fuel Control

1. DTCs P0101, P0102, P0103, P0112, P0113, P0117, P0118, P0502, P0503 are not set.
2. The minimum air temperature is more than -7°C (+19°F).
3. The start-up engine coolant temperature (ECT) is less than 8°C (46°F).
4. The engine run time is between 30 seconds and 30 minutes.
5. The vehicle has traveled more than 0.8 kilometers (0.5 miles) at more than 8 km/h (5 mph).
6. The mass air flow (MAF) is between 20-75 g/s, with the average more than 30 g/s.
7. This DTC runs once per ignition cycle within the enabling conditions in a one second loop.

1. The calibrated amount of air flow has been met.
2. The calibrated amount of engine run time has been met.
3. The calibrated vehicle speed and distance have been met.
4. The minimum ECT for Closed Loop of 8°C (46°F) has not been met.

1. The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
2. 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.

1. The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
2. A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
3. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
4. Clear the MIL and the DTC with a scan tool.

DTC P0125

An engine coolant temperature (ECT) sensor monitors the temperature of the coolant. This input is used by the engine control module (ECM) for engine control and as an enabling criteria for some diagnostics.

The air flow coming into the engine is accumulated and used to determine if the vehicle has been driven within the conditions that would allow the engine coolant to heat up normally to the thermostat regulating temperature. If the coolant temperature does not increase normally or does not reach the regulating temperature of the thermostat, the diagnostics that use ECT as enabling criteria may not run when expected.

This DTC will only run once per ignition cycle within the enabling conditions. If the ECM detects the calibrated amount of air flow, vehicle speed and distance, and engine run time have been met, and the ECT has not met the minimum thermostat regulating temperature, DTC P0128 sets.

This diagnostic procedure supports the following DTC

DTC P0128 Engine Coolant Temperature (ECT) Below Thermostat Regulating Temperature

1. DTCs P0101, P0102, P0103, P0112, P0113, P0117, P0118, P0502, P0503 are not set.
2. The startup ECT is less than 80°C (176°F).
3. The intake air temperature (IAT) is more than -7°C (+19°F).
4. The engine run time is between 30 seconds and 30 minutes.
5. The vehicle is driven more than 0.8 kilometers (0.5 miles) at more than 8 km/h (5 mph).
6. The mass air flow (MAF) is between 20-75 g/s, with the average more than 30 g/s.

The ECM detects that

1. The calibrated amount of engine run time has been met
2. The calibrated amount of engine air flow has been met
3. The calibrated vehicle speed and distance have been met.
4. The calibrated ECT of 80°C (176°F) has not been met

1. The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
2. 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.

1. The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
2. A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
3. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
4. Clear the MIL and the DTC with a scan tool.

DTC P0128

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, and low HO2S voltage indicates a lean exhaust stream. If the ECM detects that HO2S 1 voltage stays between a specified range, DTC P0130 will set.

This diagnostic procedure supports the following DTC

DTC P0130 Circuit Sensor 1

1. DTCs P0106, P0107, P0108, P0112, P0113, P0117, P0118, P0122, P0123, P0125, P0171, P0172, P0300, P0336, P0340, P0341, P0455, P0500, P0601, P0602, P0606, P0641, P0722, P0723 are not set.
2. The TP Angle parameter is more than 6.3 percent.
3. The Engine Run Time parameter is more than 60 seconds.
4. DTC P0130 runs continuously when the above conditions are met.

1. The ECM detects that the HO2S 1 voltage parameter is between 300-600 mV.
2. DTC P0130 sets within 50 seconds when the above condition is met.

1. The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
2. 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.
3. The control module commands the Loop Status open.

1. The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
2. A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
3. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
4. Clear the MIL and the DTC with a scan tool.

The number below refers to the step number on the diagnostic table.

1. 2: If the voltage is varying above and below the specified range, the conditions is not present.

DTC P0130

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, and low HO2S voltage indicates a lean exhaust stream. If the ECM detects an HO2S 1 voltage that stays below a specified value, DTC P0131 will set.

This diagnostic procedure supports the following DTC

DTC P0131 Circuit Low Voltage Sensor 1

1. DTCs P0106, P0107, P0108, P0112, P0113, P0117, P0118, P0122, P0123, P0125, P0171, P0172, P0300, P0336, P0340, P0341, P0455, P0500, P0601, P0602, P0606, P0641, P0722, P0723 are not set.
2. The Loop Status parameter is closed.
3. The Air Fuel Ratio parameter is between 14.5:1 and 14.8:1.
4. The transmission is in Drive with automatic transmission.
5. DTC P0131 runs continuously when the above conditions are met.

Lean Test

1. The ECM detects that the HO2S 1 voltage parameter is less than 291 mV.
2. DTC P0131 sets during the lean test within 100 seconds when the above condition is met.

OR

Power Enrichment Test

1. The ECM detects that the HO2S 1 voltage parameter is less than 291 mV.
2. DTC P0131 sets during the power enrichment test within 10 seconds when the above condition is met.

1. The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
2. 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.
3. The control module commands the Loop Status open.

1. The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
2. A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
3. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
4. Clear the MIL and the DTC with a scan tool.

The number below refers to the step number on the diagnostic table.

1. 2: If the voltage is varying above and below the specified range, the condition is not present.

DTC P0131

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, and low HO2S voltage indicates a lean exhaust stream. If the ECM detects that HO2S 1 voltage stays above a specified value, DTC P0132 will set.

This diagnostic procedure supports the following DTC

DTC P0132 Circuit High Voltage Sensor 1

1. DTCs P0106, P0107, P0108, P0112, P0113, P0117, P0118, P0122, P0123, P0125, P0171, P0172, P0300, P0336, P0340, P0341, P0455, P0500 P0601, P0602, P0606, P0641, P0722, P0723 are not set.
2. The Loop Status parameter is closed.
3. The Air Fuel Ratio parameter is between 14.5:1 and 14.8:1.
4. The transmission is in Drive with automatic transmission.
5. DTC P0132 runs continuously when the above conditions are met.

Rich Test

1. The ECM detects that the HO2S 1 voltage parameter is more than 786 mV.
2. DTC P0132 sets during the rich test within 100 seconds when the above condition is met.

Decel Fuel Cutoff Test

1. The ECM detects that the HO2S 1 voltage parameter is more than 586 mV.
2. DTC P0132 sets during the decel fuel cutoff test within 10 seconds when the above condition is met.

1. The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
2. 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.
3. The control module commands the Loop Status open.

1. The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
2. A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
3. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
4. Clear the MIL and the DTC with a scan tool.

The number below refers to the step number on the diagnostic table.

1. 2: If the voltage is varying above and below the specified range, the condition is not present.

DTC P0132

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. This diagnostic will only run once per ignition cycle. The ECM monitors the rich-to-lean and lean-to-rich transition time. A transition is defined as, the HO2S voltage changes from above 600 mV to below 300 mV or from below 300 mV to above 600 mV. If the ECM detects that the transition time is too long, DTC P0133 will set.

This diagnostic procedure supports the following DTC

DTC P0133 Slow Response Sensor 1

1. DTCs P0037, P0038, P0106, P0107, P0108, P0112, P0113, P0117, P0118, P0122, P0123, P0125, P0130, P0131, P0132, P0134, P0137, P0138, P0140, P0171, P0172, P0300, P0336, P0340, P0341, P0455, P0500, P0601, P0602, P0606, P0641, P0722, P0723, P1133, P1134 are not set.
2. The Air Flow parameter is between 7-25 g/s.
3. The Engine Speed parameter is between 1,500-3,200 RPM.
4. The Loop Status parameter is closed.
5. DTC P0133 runs once per drive cycle when the above conditions are met for 100 seconds.

1. The ECM detects that the HO2S 1 Lean/Rich average transition time is more than 200 milliseconds or the Rich/Lean average transition time is more than 130 milliseconds.
2. DTC P0133 sets within 60 seconds when the above condition is met.

1. The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
2. 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.

1. The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
2. A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
3. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
4. Clear the MIL and the DTC with a scan tool.

DTC P0133

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 of 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, and low HO2S voltage indicates a lean exhaust stream. If the ECM detects that HO2S 1 voltage stays between a specified range, DTC P0134 will set.

This diagnostic procedure supports the following DTC

DTC P0134 HO2S Circuit Insufficient Activity Sensor 1

1. DTCs P0106, P0107, P0108, P0112, P0113, P0117, P0118, P0122, P0123, P0125, P0171, P0172, P0300, P0336, P0340, P0341, P0455, P0500, P0601, P0602, P0606, P0641, P0722, P0723 are not set.
2. The Engine Run Time parameter is more than 60 seconds.
3. DTC P0134 runs continuously when the above conditions are met.

1. The ECM detects that the HO2S 1 voltage parameter is between 391-491 mV.
2. DTC P0134 sets within 100 seconds when the above condition is met.

1. The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
2. 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.
3. The control module commands the Loop Status open.

1. The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
2. A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
3. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
4. Clear the MIL and the DTC with a scan tool.

The number below refers to the step number on the diagnostic table.

1. 2: If the voltage is varying above and below the specified range, the condition is not present.

DTC P0134

The heated oxygen sensor (HO2S) must reach operating temperature to provide an accurate voltage signal. A heating element inside the HO2S minimizes the time required for the sensor to reach operating temperature. Voltage is provided to the heater by the ignition 1 voltage circuit through a fuse. With the engine running, ground is provided to the heater by the HO2S heater low control circuit, through a low side driver within the engine control module (ECM). The ECM commands the heater ON or OFF to maintain a specific HO2S operating temperature range. The ECM monitors the current flow through the heater for diagnosis. If the ECM detects that the current is above or below a specified range, DTCs P0135 sets.

This diagnostic procedure supports the following DTC

DTC P0135 HO2S Heater Performance Sensor 1

1. The Ignition 1 parameter is more than 10.9 volts.
2. The engine is running.
3. The affected HO2S Heater Command parameter is ON.
4. DTC P0135 runs twice per drive cycle when the above conditions are met.

1. The ECM detects that the affected HO2S Heater Current parameter is more than 1.502 amps or less than 0.249 amps.
2. DTC P0135 sets within 5 seconds when the above condition is met.

1. The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
2. 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.

1. The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
2. A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
3. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
4. Clear the MIL and the DTC with a scan tool.

DTC P0135

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.

The HO2S 2 is used for catalyst monitoring. This diagnostic runs once per ignition cycle. This diagnostic consists of 2 tests, a passive test and an intrusive test. During the passive test, if the HO2S 2 voltage transitions below 300 mV and above 725 mV, the DTC will pass for this ignition cycle. If the DTC does not pass during the passive test, the intrusive test will begin. During the intrusive test, the control module will force the air-to-fuel ratio rich and/or lean. The control module then waits for a predicted response from the HO2S. If the HO2S voltage transitions below 300 mV and/or above 725 mV, the DTC will pass for this ignition cycle. If the control module does not receive the expected response from the HO2S, DTC P0136 will set.

This diagnostic procedure supports the following DTC

DTC P0136 HO2S Circuit Sensor 2

DTCs P0068, P0106, P0107, P0108, P0112, P0113, P0117, P0118, P0120, P0122, P0123, P0125, P0128, P0130, P0131, P0132, P0137, P0138, P0140, P0141, P0171, P0201-P0204, P0220, P0300, P0315, P0336, P0442, P0446, P0452, P0453, P0455, P0496, P0506, P0507, P0601, P0602, P0604, P0606, P0641, P0651, P1134, P1516, P1621, P1680, P1681, P2101, P2120, P2125, P2135, P2138, P2176 are not set.

Passive Test

1. The engine is running.
2. The Engine Run Time parameter is less than 13.3 minutes.

Intrusive Test

1. The Engine Run Time parameter is more than 13.3 minutes.
2. The ignition 1 Signal parameter is between 11-18 volts.
3. The Engine Speed parameter is between 1,000-5,000 RPM.
4. The Vehicle Speed parameter is between 32-128 km/h (20-80 mph).
5. The Short Term FT parameter is between -10 and +10 percent.
6. The Air Flow Calculated parameter is between 14-100 g/s.
7. The maximum number of intrusive attempts is less than 25.
8. DTC P0136 runs continuously when the above conditions have been met for one second.

1. The ECM detects that the HO2S 2 did not transition below 300 mV and above 725 mV during the passive test.
2. One of the following tests fail: The Lean Intrusive Test The ECM detects that the HO2S 2 is more than 300 mV for 12 seconds. The HO2S 1 is less than 300 mV. The Rich Intrusive Test The ECM detects that the HO2S 2 is less than 725 mV for 12 seconds. The HO2S 1 is more than 600 mV.
3. DTC P0136 sets within 60 seconds when the above conditions are met.

1. The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
2. 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.

1. The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
2. A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
3. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
4. Clear the MIL and the DTC with a scan tool.

The number below refers to the step number on the diagnostic table.

1. 2: If the voltage does not change more that the specified value, the condition is present.

DTC P0136

See also:
• Engine Controls Schematics
• Engine Control Module (ECM) Connector End Views
• Engine Controls Connector End Views
• Diagnostic System Check - Vehicle
• Testing for Intermittent Conditions and Poor Connections
• Circuit Testing
• Wiring Repairs
• Probing Electrical Connectors
• Connector Repairs
• Control Module References
• Diagnostic Trouble Code (DTC) List - Vehicle
• Intermittent Conditions
• Checking Aftermarket Accessories
• Inducing Intermittent Fault Conditions
• Temperature vs Resistance
• Restricted Exhaust
• Altitude vs Barometric Pressure
• DTC P1516
• DTC P2135
• Measuring Voltage Drop
• Measuring Voltage
• Testing for Short to Ground
• Timing Chain, Sprockets, and/or Tensioner Replacement
• Engine Compression Test
• Using Connector Test Adapters
• Draining and Filling Cooling System (2.0L (LSJ))
• Thermostat Diagnosis
• Scan Tool Data List
• Silicon Contamination of Heated Oxygen Sensors Notice
• Fuel System Diagnosis
• Oil Consumption Diagnosis
• Loss of Coolant
• DTC P0106