Engine Controls - 2.2l (DTC p2119 to p2176) Chevrolet Cobalt I

Circuit Description

During Battery Saver mode, the engine control module (ECM) determines if the throttle plate is returning to the correct de-energized position. If the ECM determines the throttle plate is not at the correct position during Battery Saver mode, this DTC is set.

DTC Descriptor

This diagnostic procedure supports the following DTC

DTC P2119 Throttle Closed Position Performance

Conditions for Running the DTC

1. The ignition is ON, and the engine is OFF.
2. The ignition voltage is more than 8.5 volts.
3. The Battery Saver mode is active.
4. DTC P2119 runs once when the above conditions are met.

Conditions for Setting the DTC

1. The ECM detects that the throttle blade is not returning to the rest position.
2. The above condition is present for more than 1.5 seconds.

Action Taken When the DTC Sets

1. The ECM stores conditions which were present when the DTC set as Failure Records only.
2. This information will not be stored as Freeze Frame Records.

Conditions for Clearing the MIL/DTC

1. The DTC becomes history when the conditions for setting the DTC are no longer present.
2. The history DTC clears after 40 malfunction free warm-up cycles.
3. The ECM receives a clear code command from the scan tool.

Diagnostic Aids

Inspect for mechanical conditions or binding that may be temperature related. Components may not move freely in extreme heat or cold due to the presence of contaminants or ice formation.

Test Description

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

1. 8: More than one electronic temperature control (ETC) system related DTC may set. This is 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 P2119

The accelerator pedal position (APP) sensors 1 and 2 are located within the accelerator pedal 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 accelerator pedal movement. The APP sensor 1 signal voltage at rest position is near the low reference and increases as the pedal is actuated. The APP sensor 2 signal voltage at rest position is near the 5-volt reference and decreases as the pedal is actuated. When APP sensor 1 signal voltage is not within the predicted range, this code sets.

This diagnostic procedure supports the following DTC

DTC P2120 Accelerator Pedal Position (APP) Sensor 1 Circuit

1. The ignition is ON.
2. The ignition voltage is greater than 5.23 volts.
3. DTC P0641 is not set.
4. DTC P2120 runs continuously when the above conditions are met.

The APP sensor 1 voltage is less than 0.13 volt or more than 4.87 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 P2120

The accelerator pedal position (APP) sensor 1 and sensor 2 are located within the accelerator pedal assembly. Each sensor has the following circuits

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

This provides the engine control module (ECM) with a signal voltage proportional to accelerator pedal movement. The APP sensor 1 signal voltage at rest position is near the low reference and increases as the pedal is actuated. The APP sensor 2 signal voltage at rest position is near the 5-volt reference and decreases as the pedal is actuated. If the ECM detects the APP sensor 1 signal voltage is not within the predicted range, DTC P2122 sets.

This diagnostic procedure supports the following DTC

DTC P2122 Accelerator Pedal Position (APP) Sensor 1 Circuit Low Voltage

1. The ignition is ON.
2. The ignition voltage is more than 5.23 volts.
3. DTC P0641 is not set.
4. DTC P2122 runs continuously when the above conditions are met.

The ECM detects that the APP sensor 1 voltage is less than 0.13 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 P2122

The accelerator pedal position (APP) sensor 1 and sensor 2 are located within the accelerator pedal assembly. Each sensor has the following circuits

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

This provides the engine control module (ECM) with a signal voltage proportional to accelerator pedal movement. The APP sensor 1 signal voltage at rest position is near the low reference and increases as the pedal is actuated. The APP sensor 2 signal voltage at rest position is near the 5-volt reference and decreases as the pedal is actuated. If the ECM detects the APP sensor 1 signal voltage is not within the predicted range, DTC P2123 sets.

This diagnostic procedure supports the following DTC

DTC P2123 Accelerator Pedal Position (APP) Sensor 1 Circuit High Voltage

1. The ignition is ON.
2. The ignition voltage is more than 5.23 volts.
3. DTC P0641 is not set.
4. DTC P2123 runs continuously when the above conditions are met.

The ECM detects that the APP sensor 1 voltage is more than 4.87 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 P2123

The accelerator pedal position (APP) sensors 1 and 2 are located within the accelerator pedal 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 accelerator pedal movement. The APP sensor 1 signal voltage at rest position is near the low reference and increases as the pedal is actuated. The APP sensor 2 signal voltage at rest position is near the 5-volt reference and decreases as the pedal is actuated. When the APP sensor 2 signal voltage is not within the predicted range, this code sets.

This diagnostic procedure supports the following DTC

DTC P2125 Accelerator Pedal Position (APP) Sensor 2 Circuit

1. The ignition is ON.
2. The ignition voltage is greater than 5.23 volts.
3. DTC P0641 is not set.
4. DTC P2125 runs continuously when the above conditions are met.

The APP sensor 2 voltage is less than 0.13 volt or more than 4.87 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 P2125

The accelerator pedal position (APP) sensor 1 and sensor 2 are located within the accelerator pedal 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 accelerator pedal movement. The APP sensor 1 signal voltage at rest position is near the low reference and increases as the pedal is actuated. The APP sensor 2 signal voltage at rest position is near the 5-volt reference and decreases as the pedal is actuated. If the ECM detects that the APP sensor 2 signal voltage is not within the predicted range, DTC P2127 sets.

This diagnostic procedure supports the following DTC

DTC P2127 Accelerator Pedal Position (APP) Sensor 2 Circuit Low Voltage

1. The ignition is ON.
2. The ignition voltage is more than 5.23 volts.
3. DTC P0641 is not set.
4. DTC P2127 runs continuously when the above conditions are met.

The ECM detects that the APP sensor 2 voltage is less than 0.13 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 P2127

The accelerator pedal position (APP) sensor 1 and sensor 2 are located within the accelerator pedal 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 accelerator pedal movement. The APP sensor 1 signal voltage at rest position is near the low reference and increases as the pedal is actuated. The APP sensor 2 signal voltage at rest position is near the 5-volt reference and decreases as the pedal is actuated. If the ECM detects that the APP sensor 2 signal voltage is not within the predicted range, DTC P2128 sets.

This diagnostic procedure supports the following DTC

DTC P2128 Accelerator Pedal Position (APP) Sensor 2 Circuit High Voltage

1. The ignition is ON.
2. The ignition voltage is more than 5.23 volts.
3. DTC P0641 is not set.
4. DTC P2128 runs continuously when the above conditions are met.

The ECM detects that the APP sensor 2 voltage is more than 4.87 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 P2128

The throttle actuator control assembly has 2 throttle position (TP) sensors mounted within the assembly. The engine control module (ECM) provides individual signal, ground, and 5-volt reference circuits to each sensor. Both sensors operate within a voltage range between 0.35-4.65 volts. When the throttle is opened from 0-100 percent, one sensor signal voltage increases while the other decreases. The signal circuit for TP sensor 1 is referenced to ground, and the signal circuit for TP sensor 2 is pulled up to 5 volts within the ECM.

This diagnostic procedure supports the following DTC

DTC P2135 Throttle Position (TP) Sensor 1-2 Correlation

1. The ignition is ON.
2. DTCs P0120, P0220, P0641, P0651 are not set.
3. The ignition voltage is greater than 5.23 volts.
4. DTC P2135 runs continuously when the above conditions are met.

1. The difference between the TP sensor 1 and TP sensor 2 exceeds a predetermined value.
2. The above condition is present for more than 2 seconds.

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.

If the DTC is determined to be intermittent, refer to Intermittent Conditions .

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

1. 6: This step determines the integrity of the 5-volt reference and ground circuits of the TP sensors.
2. 7: This step determines if the 5-volt reference circuit or the sensor ground circuit is the cause of the DTC.
3. 8: If the scan tool displays 100 percent for the TP sensor 1 and the TP sensor 2 angle, this indicates that the TP sensor signal circuits are not the cause of the DTC.
4. 9: This step tests for excessive resistance in the TP sensor 5-volt reference circuit between the TP sensor harness connector and the ECM harness connector.
5. 10: This step tests for excessive resistance in the TP sensor ground circuit between the TP sensor harness connector and the ECM harness connector.
6. 11: This step tests for the TP sensor signal circuits for being shorted to another circuit in the ECM wiring harness between the ECM and the TP sensor wiring harness.
7. 16: When the ECM detects a condition within the throttle control system, more than one related DTC may set. This is 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 P2135

The accelerator pedal position (APP) sensors 1 and 2 are located within the accelerator pedal 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 accelerator pedal movement. The APP sensor 1 signal voltage at rest position is near the low reference and increases as the pedal is actuated. The APP sensor 2 signal voltage at rest position is near the 5-volt reference and decreases as the pedal is actuated.

This diagnostic procedure supports the following DTC

DTC P2138 Accelerator Pedal Position (APP) Sensor 1-2 Correlation

1. The battery voltage is more than 5.23 volts.
2. DTCs P0641, P0651, P2120, P2125 are not set.
3. The accelerator pedal is leaving the idle position.
4. DTC P2138 runs continuously when the above conditions are met.

1. The voltage difference between APP sensor 1 and APP sensor 2 exceeds a predetermined value.
2. The above condition is met for more than 2 seconds.

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 turns OFF the MIL after 3 consecutive drive trips that the diagnostic runs and does not fail.
2. A History DTC clears after 40 consecutive warm up cycles in which no failures are reported by this diagnostic or any other emission related diagnostic.
3. The scan tool clears the MIL/DTC.

1. The ECM compares the signal of each of the APP sensor to each other throughout the entire range of operation. Clear the DTCs and actuate the pedal through the entire range with the ignition ON and the engine OFF.
2. Use the J 35616 Connector Test Adapter Kit for any test that requires probing the ECM harness connector or a component harness connector. Using this kit will prevent damage to the harness connector terminals.
3. For intermittent conditions, refer to «Testing for Intermittent Conditions and Poor Connections»(/chevrolet/cobalt/i-2004-2010/remont/electrical-component-locations/#wiring-systems-electrical-power-management__testing-for-intermittent-conditions-and-poor) .

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

1. 2: Any circuit faults on either APP sensor 1 or 2 will set one of the DTCs listed. Refer to the appropriate table for diagnosis.

DTC P2138

The commanded throttle position is compared to the actual throttle position based on accelerator pedal position and possibly other limiting factors. Both values should be within a calibrated range of each other. The engine control module (ECM) continuously monitors the commanded and actual throttle positions. This DTC sets if the values are greater than the calibrated range.

This diagnostic procedure supports the following DTC

DTC P2176 Minimum Throttle Position Not Learned

1. The ignition is ON.
2. DTC P2176 runs once per key cycle.

1. The difference between the predicted and the actual throttle position is more than a calibrated amount.
2. The above condition is met for more than 1.5 seconds.

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 turns OFF the MIL after 3 consecutive drive trips that the diagnostic runs and passes.
2. A History DTC clears after 40 consecutive warm-up cycles in which there are no failures reported of this diagnostic or any other emission related diagnostic.
3. The scan tool clears the MIL/DTC.

1. The throttle valve is spring loaded to a slightly open position. This is referred to as the rest position.
2. The throttle valve should not be completely closed nor should they be open any more than the specified amount.
3. The throttle valve should move open and to the closed position without binding under the normal spring pressure.
4. The throttle should NOT be free to move open or closed WITHOUT spring pressure.
5. Replace the throttle body if any of these conditions are found.

1. The scan tool has the ability to operate the throttle control system using Special Functions. Actuate the throttle valve using the throttle blade control function located in the TAC System menu. This function will operate the throttle valve through the entire range in order to determine if the throttle body and system operate correctly.
2. Inspect for the following conditions: Use the J 35616 Connector Test Adapter Kit for any test that requires probing the ECM harness connector or a component harness connector. Poor connections at the ECM or at the component-Inspect the harness connectors for a poor terminal to wire connection. Refer to «Testing for Intermittent Conditions and Poor Connections»(/chevrolet/cobalt/i-2004-2010/remont/electrical-component-locations/#wiring-systems-electrical-power-management__testing-for-intermittent-conditions-and-poor) in Wiring Systems for the proper procedure. For an intermittent condition, refer to «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. 8: The throttle valve is spring loaded in a slightly open position and should move in either direction without binding. The throttle valve should always be under spring pressure.
2. 11: When the ignition is turned ON, the PCM operates the throttle control motor to verify the integrity of the system prior to start-up. This can be seen by the momentary flash of the test lamp as the ignition is turned ON.

DTC P2176

See also:
• Engine Controls Schematics
• Engine Control Module (ECM) Connector End Views
• Engine Controls Connector End Views
• Diagnostic System Check - Vehicle
• Diagnostic Trouble Code (DTC) List - Vehicle
• Intermittent Conditions
• Circuit Testing
• Wiring Repairs
• Testing for Intermittent Conditions and Poor Connections
• Connector Repairs
• Accelerator Controls Pedal Replacement
• Control Module References