Diagnostic Trouble Code (DTC) P2066
Fuel Level Sensor 2 Performance
Circuit Description
The Engine Control Module (ECM) uses the signal from the fuel level sensor to calculate expected vapor pressure within the fuel system. Vapor pressure varies as the fuel level changes. The fuel level signal is also used to determine if the fuel level is too high or too low to be able to detect Evaporative Emission (EVAP) system faults. This Diagnostic Trouble Code (DTC) indicates the fuel level stuck.
Conditions for Running the DTC
- Engine is running.
- Battery voltage is between 11 V and 16 V.
- No vehicle speed sensor error.
- Difference between calculated fuel consumption and measured fuel level change is greater than 1 L.
Conditions for Setting the DTC
- Fuel level change after refueling is less than 1 L.
Action Taken When the DTC Sets
- The Malfunction Indicator Lamp (MIL) will illuminate.
- The ECM will record operating conditions at the time the disgnostic fails. This information will be stored in Failure Records buffers.
- A history DTC is stored.
Conditions for Clearing the MIL/DTC
- The MIL will turn off at the end of 3 consecutive ignition cycles in which the disgnostic runs without a fault.
- A history DTC will clear after 40 consecutive warm-up cycles without a fault.
- DTC(s) can be cleared by using a scan tool.
Diagnostic Aids
An intermittent may be caused by a poor connection, rubbed-through wire insulation or a wire broken inside the rubber.
Check for a poor connection or damaged ECM harness. Inspect the fuel level circuit terminal for the following conditions:
- Improper mating.
- Broken locks.
- Improperly formed.
- Damaged terminals.
- Poor terminal-to-wire connection.
- Damaged harness.
DTC P2066 - Fuel Level Sensor 2 Performance
| Step | Action | Value(s) | Yes | No |
| 1 | Perform the Diagnostic System Check. Is the system check complete? | - | Go to Step 2 | |
| 2 | - Install a scan tool to the Data Link Connector (DLC).
- Start the engine and operate the vehicle over the specified mileage.
Is any of the Diagnostic trouble Codes (DTCs) P2067 or P2068 set? | - | Go to Applicable DTC table | Go to Step 3 |
| 3 | - Turn the ignition OFF.
- Disconnect the fuel pump connector.
- Turn the ignition ON.
- Using a voltmeter, measure the fuel level signal voltage at the fuel level sensor connector terminal 3.
Is the voltage within the specified value? | 4-5 V | Go to Step 4 | Go to Step 5 |
| 4 | - Disconnect the Engine Control Module (ECM).
- Check the fuel level sensor ground circuit for an open between terminal 2 of the fuel sensor connector and terminal 76 of the ECM and repair as needed.
Is the repair complete? | - | Go to Step 10 | Go to Step 6 |
| 5 | Using a voltmeter, measure the voltage at the ECM connector J1 terminal 76 by back-probing the ECM connector. Is the voltage within the specified value? | 4-5 V | Go to Step 8 | Go to Step 9 |
| 6 | - Remove the fuel pump from the fuel tank.
- Reconnect the fuel pump connector.
- Turn the ignition ON.
- Monitor the fuel level sensor parameter on the scan tool while moving the fuel sensor float from empty position to full position.
- Repeat procedure 4 several times.
Does the fuel level sensor vale on the scan tool increase and then decrease steadily when the float is moved? | - | | Go to Step 7 |
| 7 | - Turn the ignition OFF.
- Replace the fuel pump assembly.
Is the repair complete? | - | Go to Step 10 | - |
| 8 | - Turn the ignition OFF.
- Disconnect the ECM connector.
- Check the fuel level signal circuit fir an open or short to ground between terminal 35 and fuel pump harness connector terminal 3 and repair as needed.
Is the repair complete? | - | Go to Step 10 | - |
| 9 | - Turn the ignition OFF.
- Replace the ECM.
Is the repair complete? | - | Go to Step 10 | - |
| 10 | - Using the scan tool, clear the Diagnostic Trouble Codes (DTCs).
- Start the engine and idle at normal operating temperature.
- Operate the vehicle within the conditions for setting the DTC as specifiec in the supporting text.
Does the scan tool indicate that this diagnostic run and passed? | - | Go to Step 11 | Go to Step 2 |
| 11 | Check if any additional DTCs are set. Are any DTCs displayed that have not been diagnosed? | - | Go to Applicable DTC table | System OK |
Diagnostic Trouble Code (DTC) P2067
Fuel Level Sensor 2 Circuit Low Voltage
Circuit Description
The engine control module(ECM) uses the fuel level input from the Fuel Level Sensor to calculate expected vapor pressures within the fuel system. Vapor pressure vary as the fuel level changes. Vapor pressure is critical in determining if the evaporative emission (EVAP) system is operating properly. Fuel Level is also used to determine if the Fuel level is too high or too low to be able to accurately detect EVAP system faults. This Diagnostic Trouble Code(DTC) detects a stuck fuel level sender.
Conditions for Running the DTC
- Engine is running.
- Battery voltage is between 11 V and 16 V.
- No vehicle speed sensor error.
- Difference between calculated fuel consumption and measured fuel level change is greater than 1 L.
Conditions for Setting the DTC
- Fuel tank level signal is less than 0.25 V.
Action Taken When the DTC Sets
- The Malfunction Indicator Lamp (MIL) will be illuminated after 3 valid driving cycles.
- The ECM will record operating conditions at the time the diagnostic fail. This information will be stored in the Freeze Frame and Failure Records buffers.
- A history DTC is stored.
Conditions for Clearing the MIL/DTC
- The MIL will turn off after three or four consecutive driving cycles in which the diagnostic runs without a fault.
- A history DTC will clear after 40 consecutive warm up cycles without a fault.
- DTC(s) can be cleared by using the scan tool.
- Disconnecting the ECM battery feed for 10 seconds.
Diagnostic Aids
Inspect harness connectors for backed-out terminal, improper mating, broken locks, improperly formed or damaged terminals, and poor terminal-to-wire connection.
Inspect the wiring harness for damage.
A stuck Fuel Level Sensor may cause the DTC to set. If DTC P0462 cannot be duplicated, the information included in the Freeze Frame data can be useful in determining vehicle operating conditions when the DTC was first set.
DTC P2067 - Fuel Level Sensor 2 Circuit Low Voltage
| Step | Action | Value(s) | Yes | No |
| 1 | Perform the Diagnostic System Check. Is the system check complete? | - | Go to Step 2 | |
| 2 | - Turn the ignition switch to ON.
- Install a scan tool.
- Operate the vehicle within Freeze Frame conditions as noted.
Is the Diagnostic Trouble Code (DTC) P0462 set? | - | Go to Step 3 | |
| 3 | - Disconnect the fuel sender electircal connector from the fuel pump.
- Using a digital voltmeter (DVM), measure the voltage in the signal circuit at terminal 3.
Is the voltage within the specified value? | 0.2-4.8V | Go to Step 4 | Go to Step 6 |
| 4 | Check for a proper ground connection at the fuel tank and repair as necessary. Is a repair necessary? | - | Go to Step 11 | Go to Step 5 |
| 5 | - Remove the fuel sender from the fuel tank.
- Reconnect the fuel sender electrical connector.
- Monitor the Fuel Level Sensor parameter on the scan tool while moving the Fuel Level Sensor float from the empty position to the full position.
- Repeat the procedure several times.
Does the Fuel Level Sensor value on the scan tool increase and then decrease steadily when the float is moved? | - | | Go to Step 8 |
| 6 | Check for an open or short to ground in the Fuel Level Sensor circuit and repair as necessary. Is the repair necessary? | - | Go to Step 7 | Go to Step 9 |
| 7 | Repair the open or short to ground in the Fuel Level Sensor circuit between the Fuel Level Sensor harness connector and the Fuel Level Sensor. Is the repair complete? | - | Go to Step 11 | - |
| 8 | Replace the fuel sender assembly. Is the replacement complete? | - | Go to Step 11 | - |
| 9 | - Connect the fuel sender electrical connector.
- Disconnect the engine control module(ECM) connector.
- Using a digital voltmeter (DVM) measure the voltage in the signal circuit, at terminal 35.
Does the DVM read within the specified value? | 0.2-4.8V | Go to Step 10 | |
| 10 | Replace the ECM. Is the repair complete? | - | Go to Step 11 | - |
| 11 | - Using the scan tool, clear the Diagnostic Trouble Codes (DTCs).
- Start the engine and idle at normal operating temperature.
- Operate the vehicle within the conditions for setting the DTC as specifiec in the supporting text.
Does the scan tool indicate that this diagnostic ran and passed? | - | Go to Step 12 | Go to Step 2 |
| 12 | Check if any additional DTCs are set. Are any DTCs displayed that have not been diagnosed? | - | Go to Applicable DTC table | System OK |
Diagnostic Trouble Code (DTC) P2068
Fuel Level Sensor 2 Circuit High Voltage
Circuit Description
The engine control module(ECM) uses the fuel level input from the Fuel Level Sensor to calculate expected vapor pressures within the fuel system. Vapor pressure vary as the fuel level changes. Vapor pressure is critical in determining if the evaporative emission (EVAP) system is operating properly. Fuel Level is also used to determine if the Fuel level is too high or too low to be able to accurately detect EVAP system faults. This Diagnostic Trouble Code(DTC) detects a stuck fuel level sender.
Conditions for Running the DTC
- Engine is running.
- Battery voltage is between 11 V and 16 V.
- No vehicle speed sensor error.
- Difference between calculated fuel consumption and measured fuel level change is greater than 1 L.
Conditions for Setting the DTC
- Fuel tank level signal is greater than 4.2 V.
Action Taken When the DTC Sets
- The Malfunction Indicator Lamp (MIL) will be illuminated after 3 valid driving cycles.
- The ECM will record operating conditions at the time the diagnostic fail. This information will be stored in the Freeze Frame and Failure Records buffers.
- A history DTC is stored.
Conditions for Clearing the MIL/DTC
- The MIL will turn off after three or four consecutive driving cycles in which the diagnostic runs without a fault.
- A history DTC will clear after 40 consecutive warm up cycles without a fault.
- DTC(s) can be cleared by using the scan tool.
- Disconnecting the ECM battery feed for 10 seconds.
Diagnostic Aids
Inspect harness connectors for backed-out terminal, improper mating, broken locks, improperly formed or damaged terminals, and poor terminal-to-wire connection.
Inspect the wiring harness for damage.
A stuck Fuel Level Sensor may cause the DTC to set. If DTC P0463 cannot be duplicated, the information included in the Freeze Frame data can be useful in determining vehicle operating conditions when the DTC was first set.
DTC P2068 - Fuel Level Sensor 2 Circuit High Voltage
| Step | Action | Value(s) | Yes | No |
| 1 | Perform the Diagnostic System Check. Is the system check complete? | - | Go to Step 2 | |
| 2 | - Turn the ignition switch to ON.
- Install a scan tool.
- Operate the vehicle within Freeze Frame conditions as noted.
Is the Diagnostic Trouble Code (DTC) P0463 set? | - | Go to Step 3 | |
| 3 | - Disconnect the fuel sender electircal connector from the fuel pump.
- Using a digital voltmeter (DVM), measure the voltage in the signal circuit at terminal 3.
Is the voltage within the specified value? | 0.2-4.8V | Go to Step 4 | Go to Step 6 |
| 4 | Check for a proper ground connection at the fuel tank and repair as necessary. Is a repair necessary? | - | Go to Step 11 | Go to Step 5 |
| 5 | - Remove the fuel sender from the fuel tank.
- Reconnect the fuel pump electrical connector.
- Monitor the Fuel Level Sensor parameter on the scan tool while moving the Fuel Level Sensor float from the empty position to the full position.
- Repeat the procedure several times.
Does the Fuel Level Sensor value on the scan tool increase and then decrease steadily when the float is moved? | - | | Go to Step 8 |
| 6 | Check for an open or short to battery voltage in the Fuel Level Sensor circuit and repair as necessary. Is the repair necessary? | - | Go to Step 7 | Go to Step 9 |
| 7 | Repair the open or short to battery voltage in the Fuel Level Sensor circuit between the Fuel Level Sensor harness connector and the Fuel Level Sensor. Is the repair complete? | - | Go to Step 11 | - |
| 8 | Replace the fuel sender assembly. Is the replacement complete? | - | Go to Step 11 | - |
| 9 | - Connect the fuel sender electrical connector.
- Disconnect the engine control module(ECM) connector.
- Using a digital voltmeter (DVM) measure the voltage in the signal circuit, at terminal 35.
Does the DVM read within the specified value? | 0.2-4.8V | Go to Step 10 | |
| 10 | Replace the ECM. Is the repair complete? | - | Go to Step 11 | - |
| 11 | - Using the scan tool, clear the Diagnostic Trouble Codes (DTCs).
- Start the engine and idle at normal operating temperature.
- Operate the vehicle within the conditions for setting the DTC as specifiec in the supporting text.
Does the scan tool indicate that this diagnostic ran and passed? | - | Go to Step 12 | Go to Step 2 |
| 12 | Check if any additional DTCs are set. Are any DTCs displayed that have not been diagnosed? | - | Go to Applicable DTC table | System OK |
Diagnostic Trouble Code (DTC) P2096
Post Catalyst Fuel Trim System Low Limit
Circuit Description
The engine control module (ECM) supplies a voltage of about 0.45V to the oxygen sensor. The oxygen sensor (O2S) varies the voltage within a range of about 1V if the exhaust is rich, down to about 0.1V if the exhaust is lean.
This diagnosis can detect the sluggish behavior of the lean shift of HO2S1 and detect the abnormality of HO2S2 (below 0.65 volts). A malfunction is registered if the fuel trim control values exceed the maximum threshold value for the diagnosis time during fuel trim control activation phase. If catalysts are deteriorated, HO2S2 signal oscillates according to the actual lambda signal. So, the diagnosis must be considered with catalyst deterioration factor.
Conditions for Running the DTC
- HO2S2 lambda control enabled.
- No catalyst system error.
Conditions for Setting the DTC
- HO2S2 controled time is greater than 1.0 second.
Action Taken When the DTC Sets
- The Malfunction Indicator Lamp (MIL) will be illuminated after 3 valid driving cycles.
- The ECM will record operating conditions at the time the diagnostic fail. This information will be stored in the Freeze Frame and Failure Records buffers.
- A history DTC is stored.
Conditions for Clearing the MIL/DTC
- The MIL will turn off after three or four consecutive driving cycles in which the diagnostic runs without a fault.
- A history DTC will clear after 40 consecutive warm up cycles without a fault.
- DTC(s) can be cleared by using the scan tool.
- Disconnecting the ECM battery feed for 10 seconds.
Diagnostic Aids
An intermittent malfunction may be caused by a problem in the HO2S electrical circuit. Inspect the wiring harness and the components for an intermittent condition. Refer to
"Intermittent".DTC P2096 - Post Catalyst Fuel Trim System Low Limit
| Step | Action | Value(s) | Yes | No |
| 1 | Perform the Diagnostic System Check. Is the system check complete? | - | Go to Step 2 | |
| 2 | - Allow the engine to reach operating temperature.
- Operate the vehicle within the parameters specified in Conditions for Setting the DTC.
- Observe the diagnostic trouble code (DTC) information with a scan tool.
Did the DTC fail this ignition? | - | Go to Step 4 | Go to Step 3 |
| 3 | - Observe the Freeze Frame / Failure Records for this DTC.
- Turn OFF the ignition for 30 seconds.
- Start the engine.
- Operate the vehicle within the Conditions for Setting the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records.
Did the DTC fail this ignition? | - | Go to Step 4 | |
| 4 | - Operate the engine above 1,200 rpm for 30 seconds.
- Observe the appropriate rear heated oxygen sensor (HO2S) voltage with a scan tool.
Is the voltage more than the specified value? | 60 mV | Go to Step 7 | Go to Step 5 |
| 5 | - Turn OFF the ignition.
- Disconnect the appropriate HO2S.
- Turn ON the ignition, with the engine OFF.
- Observe the HO2S voltage parameter with a scan tool.
Is the voltage within the specified range? | 350~550 mV | Go to Step 12 | Go to Step 6 |
| 6 | Test the appropriate HO2S signal circuit for a short to ground. Did you find and correct the condition? | - | Go to Step 19 | Go to Step 14 |
| 7 | Inspect the rear HO2S for being connected to the correct bank of the engine. If the sensors are connected to the incorrect bank, swap the connectors as necessary. Did you find and correct the condition? | - | Go to Step 19 | Go to Step 8 |
| 8 | Move the related HO2S harnesses for the front sensor between the HO2S harness connector and the engine control module (ECM) while monitoring the appropriate HO2S lambda parameter. Does the HO2S parameter change abruptly while moving the related harnesses? | - | Go to Step 15 | Go to Step 9 |
| 9 | Move the related HO2S harnesses for the rear sensor between the HO2S harness connector and the ECM while monitoring the appropriate HO2S voltage parameter. Does the HO2S parameter change abruptly while moving the related harnesses? | - | Go to Step 15 | Go to Step 10 |
| 10 | - Turn OFF the ignition.
- Disconnect the front and rear HO2S.
- Inspect the front and rear HO2S for the following conditions:
- Damaged wiring between the HO2S and the ECM.
- Terminal corrosion or water intrusion in theHO2S harness connectors.
- The correct terminal tension.
- The HO2S is securely installed.
- Any exhaust leaks.
- Repair as necessary.
Did you find and correct the condition? | - | Go to Step 19 | Go to Step 11 |
| 11 | - Disconnect the ECM.
- Test the appropriate front HO2S circuits for being shorted together between the HO2S connector and the ECM.
Did you find and correct the condition? | - | Go to Step 19 | Go to Step 13 |
| 12 | Test for shorted terminals and for poor connections at the HO2S. Did you find and correct the condition? | - | Go to Step 19 | Go to Step 17 |
| 13 | Test for shorted terminals and for poor connections at the ECM. Did you find and correct the condition? | - | Go to Step 19 | Go to Step 16 |
| 14 | Test for shorted terminals and for poor connections at the ECM. Did you find and correct the condition? | - | Go to Step 19 | Go to Step 18 |
| 15 | Repair the circuit as necessary. Did you complete the repair? | - | Go to Step 19 | - |
| 16 | Replace the HO2S Sensor 1. Did you complete the replacement? | - | Go to Step 19 | - |
| 17 | Replace the HO2S Sensor 2. Did you complete the replacement? | - | Go to Step 19 | - |
| 18 | Replace the ECM. Did you complete the replacement? | - | Go to Step 19 | - |
| 19 | - Clear the DTCs with a scan tool.
- Turn OFF the ignition for 30 seconds.
- Start the engine.
- Operate the vehicle within the Conditions for Setting the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records.
Did the DTC fail this ignition? | - | Go to Step 2 | Go to Step 20 |
| 20 | Check if any additional DTCs are set. Are any DTCs displayed that have not been diagnosed? | - | Go to Applicable DTC table | System OK |
Diagnostic Trouble Code (DTC) P2097
Post Catalyst Fuel Trim System High Limit
Circuit Description
The engine control module (ECM) supplies a voltage of about 0.45V to the oxygen sensor. The oxygen sensor (O2S) varies the voltage within a range of about 1V if the exhaust is rich, down to about 0.1V if the exhaust is lean.
This diagnosis can detect the sluggish behavior of the lean shift of HO2S1 and detect the abnormality of HO2S2 (below 0.65 volts). A malfunction is registered if the fuel trim control values exceed the maximum threshold value for the diagnosis time during fuel trim control activation phase. If catalysts are deteriorated, HO2S2 signal oscillates according to the actual lambda signal. So, the diagnosis must be considered with catalyst deterioration factor.
Conditions for Running the DTC
- HO2S2 lambda control enabled.
- No catalyst system error.
Conditions for Setting the DTC
- HO2S2 controled time is less than 1.0 second.
Action Taken When the DTC Sets
- The Malfunction Indicator Lamp (MIL) will be illuminated after 3 valid driving cycles.
- The ECM will record operating conditions at the time the diagnostic fail. This information will be stored in the Freeze Frame and Failure Records buffers.
- A history DTC is stored.
Conditions for Clearing the MIL/DTC
- The MIL will turn off after three or four consecutive driving cycles in which the diagnostic runs without a fault.
- A history DTC will clear after 40 consecutive warm up cycles without a fault.
- DTC(s) can be cleared by using the scan tool.
- Disconnecting the ECM battery feed for 10 seconds.
Diagnostic Aids
An intermittent malfunction may be caused by a problem in the HO2S electrical circuit. Inspect the wiring harness and the components for an intermittent condition. Refer to
"Intermittent".DTC P2097 - Post Catalyst Fuel Trim System High Limit
| Step | Action | Value(s) | Yes | No |
| 1 | Did you perform the Diagnostic System Check? | - | Go to Step 2 | |
| 2 | - Observe the Freeze Frame/Failure Records for this DTC.
- Turn OFF the ignition for 30 seconds.
- Start the engine.
- Operate the vehicle within the Conditions for Setting the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records.
Did the DTC fail this ignition? | - | Go to Step 3 | |
| 3 | - Operate the engine above 1,200 RPM for 30 seconds.
- Observe the appropriate rear HO2S voltage with a scan tool.
Is the voltage less than the specified value? | 1050 mV | Go to Step 6 | Go to Step 4 |
| 4 | - Turn OFF the ignition.
- Disconnect the appropriate HO2S.
- Turn ON the ignition with the engine OFF.
- Observe the HO2S voltage parameter with a scan tool.
Is the voltage within the specified range? | 350-550 mV | Go to Step 11 | Go to Step 5 |
| 5 | Test the appropriate HO2S signal circuit for a short to voltage. Did you find and correct the condition? | - | Go to Step 18 | Go to Step 13 |
| 6 | Inspect the rear heated oxygen sensors for being connected to the correct bank of the engine. If the sensors are connected to the incorrect bank, swap the connectors as necessary. Did you find and correct the condition? | - | Go to Step 18 | Go to Step 7 |
| 7 | Move the related HO2S harnesses for the front sensor between the HO2S harness connector and the engine control module (ECM) while monitoring the appropriate HO2S lambda parameter. Does the HO2S parameter change abruptly while moving the related harnesses? | - | Go to Step 14 | Go to Step 8 |
| 8 | Move the related HO2S harnesses for the rear sensor between the HO2S harness connector and the ECM while monitoring the appropriate HO2S voltage parameter. Does the HO2S parameter change abruptly while moving the related harnesses? | - | Go to Step 14 | Go to Step 9 |
| 9 | - Turn OFF the ignition.
- Disconnect the heated oxygen sensors.
- Inspect the front and rear heated oxygen sensors for the following conditions:
- For damaged wiring between the HO2S and the ECM--An intermittent circuit condition may cause this DTC to set.
- For terminal corrosion or water intrusion in the HO2S harness connectors.
- For the correct terminal tension.
- The HO2S is securely installed.
- For any exhaust leaks.
- Repair as necessary.
Did you find and correct the condition? | - | Go to Step 18 | Go to Step 10 |
| 10 | - Disconnect the ECM.
- Test the appropriate front heated oxygen sensor circuits for being shorted together between the HO2S connector and the ECM.
Did you find and correct the condition? | - | Go to Step 18 | Go to Step 12 |
| 11 | Test for shorted terminals and for poor connections at the ECM. Did you find and correct the condition? | - | Go to Step 18 | Go to Step 16 |
| 12 | Test for shorted terminals and for poor connections at the ECM. Did you find and correct the condition? | - | Go to Step 18 | Go to Step 15 |
| 13 | Test for shorted terminals and for poor connections at the ECM. Did you find and correct the condition? | - | Go to Step 18 | Go to Step 17 |
| 14 | Repair the circuit as necessary. Did you complete the repair? | - | Go to Step 18 | - |
| 15 | Replace the HO2S Sensor 1. Did you complete the replacement? | - | Go to Step 18 | - |
| 16 | Replace the HO2S Sensor 2. Did you complete the replacement? | - | Go to Step 18 | - |
| 17 | Replace the ECM. Did you complete the replacement? | - | Go to Step 18 | - |
| 18 | - Clear the DTCs with a scan tool.
- Turn OFF the ignition for 30 seconds.
- Start the engine.
- Operate the vehicle within the Conditions for Setting the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records.
Did the DTC fail this ignition? | - | Go to Step 2 | Go to Step 19 |
| 19 | Check if any additional DTCs are set. Are there any DTCs that have not been diagnosed? | - | Go to Applicable DTC table | System OK |
Diagnostic Trouble Code (DTC) P2100
Throttle Actuator Control (TAC) Motor Control Circuit
Circuit Description
The ECM monitors and evaluates the accelerator pedal position (APP) sensors signal voltage along with other sensor inputs to determine the desired throttle opening. To control the throttle plate movement, the ECM applies a pulse width modulated (PWM) signal voltage to the throttle actuator motor through the throttle actuator motor control circuits. In addition, the ECM monitors the signal voltage applied to the throttle actuator motor control circuit. A TAC motor control circuit DTC sets if the ECM detects a fault condition in the TAC circuits or motor performance.
Conditions for Running the DTC
Conditions for Setting the DTC
- The ECM detects that its internal TAC motor output driver does not deactivate when commanded off.
Action Taken When the DTC Sets
- The Malfunction Indicator Lamp (MIL) will be illuminated as soon as the error occurs.
- The ECM will record operating conditions at the time the diagnostic fail. This information will be stored in the Freeze Frame and Failure Records buffers.
- A history DTC is stored.
Conditions for Clearing the MIL/DTC
- The MIL will turn off after three or four consecutive driving cycles in which the diagnostic runs without a fault.
- A history DTC will clear after 40 consecutive warm up cycles without a fault.
- DTC(s) can be cleared by using the scan tool.
- Disconnecting the ECM battery feed for 10 seconds.
DTC P2100 - Throttle Actuator Control (TAC) Motor Control Circuit
| Step | Action | Value(s) | Yes | No |
| 1 | Did you perform the Diagnostic System Check? | - | Go to Step 2 | |
| 2 | - Switch off the ignition for 30 seconds.
- Operate the vehicle within the conditions for running the DTC.
- Start the engine.
- Quickly depress the accelerator pedal to wide-open throttle then release pedal. Repeat this procedure several times.
- Using the Scan Tool, select the DTC display function.
Did the DTC P2100 fail this ignition? | - | Go to Step 3 | - |
| 3 | Is DTC P0121, P0122, P0123, P0221, P0222 or P0223 also set? | - | Go to applicable DTC table | - |
| 4 | - Disconnect the throttle actuator wiring connector.
- Inspect the throttle plate for the following:
- excessive dirt build-up in the throttle body,
- not in rest position,
- binding open or binding close,
- binding when moving from open to close or close to open position, and
- free to move open or close without spring pressure.
Did you find and correct the condition? | - | Go to Step 13 | Go to Step 5 |
| 5 | Inspect the engine for fault conditions that causes incorrect idle speed. Did you find and correct the condition? | - | Go to Step 13 | Go to Step 6 |
| 6 | - Switch on the ignition with the engine not running.
- Using a digital multimeter, measure the voltage between the TAC positive circuit and the ECM housing.
Is the voltage within the specified range? | 2 - 4 V | Go to Step 7 | Go to Step 9 |
| 7 | - Switch on the ignition with the engine not running.
- Using a digital multimeter, measure the voltage between the TAC positive control circuit and the ECM housing.
Is the voltage within the specified range? | 2 - 4 V | Go to Step 8 | Go to Step 9 |
| 8 | - Switch off the ignition.
- Connect a test lamp between the positive and negative control circuit of the TAC.
- Switch on the ignition for about 5 seconds then switch off while observing the test lamp.
Does the test lamp illuminate briefly each time the ignition cycles? | - | Go to Step 11 | Go to Step 10 |
| 9 | Test the TAC control circuit that measured outside the specified value for a high resistance, open circuit, short to ground or short to voltage fault condition. Did you find and correct the condition? | - | Go to Step 13 | Go to Step 12 |
| 10 | Test the positive and negative control circuits of the TAC for a shorted together fault condition. Did you find and correct the condition? | - | Go to Step 13 | Go to Step 12 |
| 11 | Replace the throttle body assembly. Did you complete the replacement? | - | Go to Step 13 | - |
| 12 | Replace the ECM. Did you complete the replacement? | - | Go to Step 13 | - |
| 13 | - Clear the DTCs with a scan tool.
- Turn OFF the ignition for 30 seconds.
- Start the engine.
- Operate the vehicle within the Conditions for Setting the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records.
Did the DTC fail this ignition? | - | Go to Step 2 | Go to Step 14 |
| 14 | Check if any additional DTCs are set. Are there any DTCs that have not been diagnosed? | - | Go to applicable DTC table | System OK |
Diagnostic Trouble Code (DTC) P2101
Throttle Actuator Position Performance
Circuit Description
The ECM monitors and evaluates the accelerator pedal position (APP) sensors signal voltage along with other sensor inputs to determine the desired throttle opening. To control the throttle plate movement, the ECM applies a pulse width modulated (PWM) signal voltage to the throttle actuator motor through the throttle actuator motor control circuits. In addition, the ECM monitors the signal voltage applied to the throttle actuator motor control circuit. A TAC motor control circuit DTC sets if the ECM detects a fault condition in the TAC circuits or motor performance.
Conditions for Running the DTC
Conditions for Setting the DTC
- The ECM detects the difference between the commanded and the altnal throttle opening is greater than map value (4 ~ 50 %).
Action Taken When the DTC Sets
- The Malfunction Indicator Lamp (MIL) will be illuminated as soon as the error occurs.
- The ECM will record operating conditions at the time the diagnostic fail. This information will be stored in the Freeze Frame and Failure Records buffers.
- A history DTC is stored.
Conditions for Clearing the MIL/DTC
- The MIL will turn off after three or four consecutive driving cycles in which the diagnostic runs without a fault.
- A history DTC will clear after 40 consecutive warm up cycles without a fault.
- DTC(s) can be cleared by using the scan tool.
- Disconnecting the ECM battery feed for 10 seconds.
DTC P2101 - Throttle Actuator Position Performance
| Step | Action | Value(s) | Yes | No |
| 1 | Did you perform the Diagnostic System Check? | - | Go to Step 2 | |
| 2 | - Switch off the ignition for 30 seconds.
- Operate the vehicle within the conditions for running the DTC.
- Start the engine.
- Quickly depress the accelerator pedal to wide-open throttle then release pedal. Repeat this procedure several times.
- Using the Scan Tool, select the DTC display function.
Did the DTC P2101 fail this ignition? | - | Go to Step 3 | - |
| 3 | Is DTC P0121, P0122, P0123, P0221, P0222 or P0223 also set? | - | Go to applicable DTC table | - |
| 4 | - Disconnect the throttle actuator wiring connector.
- Inspect the throttle plate for the following:
- excessive dirt build-up in the throttle body,
- not in rest position,
- binding open or binding close,
- binding when moving from open to close or close to open position, and
- free to move open or close without spring pressure.
Did you find and correct the condition? | - | Go to Step 13 | Go to Step 5 |
| 5 | Inspect the engine for fault conditions that causes incorrect idle speed. Did you find and correct the condition? | - | Go to Step 13 | Go to Step 6 |
| 6 | - Switch on the ignition with the engine not running.
- Using a digital multimeter, measure the voltage between the TAC positive circuit and the ECM housing.
Is the voltage within the specified range? | 2 - 4 V | Go to Step 7 | Go to Step 9 |
| 7 | - Switch on the ignition with the engine not running.
- Using a digital multimeter, measure the voltage between the TAC positive control circuit and the ECM housing.
Is the voltage within the specified range? | 2 - 4 V | Go to Step 8 | Go to Step 9 |
| 8 | - Switch off the ignition.
- Connect a test lamp between the positive and negative control circuit of the TAC.
- Switch on the ignition for about 5 seconds then switch off while observing the test lamp.
Does the test lamp illuminate briefly each time the ignition cycles? | - | Go to Step 11 | Go to Step 10 |
| 9 | Test the TAC control circuit that measured outside the specified value for a high resistance, open circuit, short to ground or short to voltage fault condition. Did you find and correct the condition? | - | Go to Step 13 | Go to Step 12 |
| 10 | Test the positive and negative control circuits of the TAC for a shorted together fault condition. Did you find and correct the condition? | - | Go to Step 13 | Go to Step 12 |
| 11 | Replace the throttle body assembly. Did you complete the replacement? | - | Go to Step 13 | - |
| 12 | Replace the ECM. Did you complete the replacement? | - | Go to Step 13 | - |
| 13 | - Clear the DTCs with a scan tool.
- Turn OFF the ignition for 30 seconds.
- Start the engine.
- Operate the vehicle within the Conditions for Setting the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records.
Did the DTC fail this ignition? | - | Go to Step 2 | Go to Step 14 |
| 14 | Check if any additional DTCs are set. Are there any DTCs that have not been diagnosed? | - | Go to applicable DTC table | System OK |
Diagnostic Trouble Code (DTC) P2107
Throttle Actuator Control (TAC) Module Internal Circuit
Circuit Description
The ECM applies 5 V to the throttle position (TP) sensor 1 through the 5 V reference circuit and the ground through the low reference circuit. TP sensor 1 and TP sensor 2 share common 5 V reference circuit and low reference circuit.
The TP sensor 1 and TP sensor 2 have individual signal circuits with opposite functionality. These signal circuits provide the ECM with a signal voltage that is proportional to the throttle plate movement. The ECM monitors and evaluates the accelerator pedal position (APP) sensors signal voltage along with other sensor inputs to determine the desired throttle opening. To control the throttle plate movement, the ECM applies a pulse width modulated (PWM) signal voltage to the throttle actuator motor through the throttle actuator motor control circuits.
Conditions for Running the DTC
- Under throttle control actuator initialization.
Conditions for Setting the DTC
- Amplification of throttl position sensor 1 is greater than 4.3242 V or less than 3.9961 V.
Action Taken When the DTC Sets
- The Malfunction Indicator Lamp (MIL) will be illuminated as soon as the error occurs.
- The ECM will record operating conditions at the time the diagnostic fail. This information will be stored in the Freeze Frame and Failure Records buffers.
- A history DTC is stored.
Conditions for Clearing the MIL/DTC
- The MIL will turn off after three or four consecutive driving cycles in which the diagnostic runs without a fault.
- A history DTC will clear after 40 consecutive warm up cycles without a fault.
- DTC(s) can be cleared by using the scan tool.
- Disconnecting the ECM battery feed for 10 seconds.
DTC P2107 - Throttle Actuator Control (TAC) Module Internal Circuit
| Step | Action | Value(s) | Yes | No |
| 1 | Did you perform the Diagnostic System Check? | - | Go to Step 2 | |
| 2 | - Switch off the ignition for 30 seconds.
- Operate the vehicle within the conditions for running the DTC.
- Start the engine.
- Using the Scan Tool, select the DTC display function.
Did the DTC P2107 fail this ignition? | - | Go to Step 3 | - |
| 3 | Replace the ECM. Did you complete the replacement? | - | Go to Step 4 | - |
| 4 | - Clear the DTCs with a scan tool.
- Turn OFF the ignition for 30 seconds.
- Start the engine.
- Operate the vehicle within the Conditions for Setting the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records.
Did the DTC fail this ignition? | - | Go to Step 2 | Go to Step 5 |
| 5 | Check if any additional DTCs are set. Are there any DTCs that have not been diagnosed? | - | Go to applicable DTC table | System OK |
Diagnostic Trouble Code (DTC) P2119
Throttle Closed Position Performance
Circuit Description
The engine control module (ECM) controls the throttle valve by applying a varying voltage to the control circuits of the throttle actuator control (TAC) motor. The ECM monitors the duty cycle that is required to actuate the throttle valve. The ECM monitors the throttle position (TP) sensors 1 and 2 to determine the actual throttle valve position.
Conditions for Running the DTC
Conditions for Setting the DTC
- Difference between throttle angle and throttle angle in the limphome air position is greater than 2.9999 %.
- Time counter throttle return spring checks is greater than 0.560 second.
or
- Difference between throttle angle and throttle angle in the limphome air position is greater than 12 %.
- Time counter throttle return spring checks is greater than 0.140 second.
Action Taken When the DTC Sets
- The Malfunction Indicator Lamp (MIL) will be illuminated as soon as the error occurs.
- The ECM will record operating conditions at the time the diagnostic fail. This information will be stored in the Freeze Frame and Failure Records buffers.
- A history DTC is stored.
Conditions for Clearing the MIL/DTC
- The MIL will turn off after three or four consecutive driving cycles in which the diagnostic runs without a fault.
- A history DTC will clear after 40 consecutive warm up cycles without a fault.
- DTC(s) can be cleared by using the scan tool.
- Disconnecting the ECM battery feed for 10 seconds.
Diagnostic Aids
- Inspect for a condition in which the throttle valve may have been held open. For example, ice may have formed in the throttle bore causing the throttle valve not to close. Observe the Freeze Frame/Failure Records.
- The throttle valve is spring loaded to a slightly open position.
- The throttle valve should not be completely closed or open any more than a specified amount.
- The throttle valve should move open and to the closed position without binding under the normal spring pressure.
- The throttle should NOT be free to move open or closed WITHOUT spring pressure.
- For an intermittent condition, refer to "Intermittents".
DTC P2119 - Throttle Closed Position Performance
| Step | Action | Value(s) | Yes | No |
| 1 | Did you perform the Diagnostic System Check? | - | Go to Step 2 | |
| 2 | - Turn ON the ignition, with the engine OFF.
- Clear the DTCs with a scan tool.
- Start the engine.
- Perform the following tests:
- Rapidly depress the accelerator pedal from the rest position to the wide open throttle position (WOT) and release pedal. Repeat the procedure several times.
- Slowly depress the accelerator pedal to WOT and then slowly return the pedal to closed throttle. Repeat the procedure several times.
- Observe the DTC information with a scan tool.
Did DTC P0121, P0122, P0123, P0221, P0222, or P0223 fail this ignition? | - | Go to applicable DTC table | Go to Step 3 |
| 3 | Did DTC P0638, and/or P2119 fail this ignition? | - | Go to Step 5 | Go to Step 4 |
| 4 | - Observe the Freeze Frame/Failure Records for this DTC.
- Turn OFF the ignition for 30 seconds.
- Start the engine.
- Operate the vehicle within the Conditions for Setting the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records.
Did the DTC fail this ignition? | - | Go to Step 5 | |
| 5 | - Turn OFF the engine.
- Turn ON the ignition, with the engine OFF.
- Observe the throttle position (TP) sensor 1 voltage parameter with a scan tool.
Is the voltage within the specified range? | 0.40-0.80 V | Go to Step 6 | |
| 6 | Observe the TP sensor 2 voltage parameter with a scan tool. Is the voltage within the specified range? | 4.7-4.1 V | Go to Step 7 | |
| 7 | - Disconnect the throttle body harness connector.
- Turn ON the ignition, with the engine OFF.
- Measure the voltage of the throttle actuator control (TAC) motor control 1 and TAC motor control 2 circuits of the throttle actuator control motor with a DMM connected to the engine control module (ECM) housing.
Is the voltage within the specified range for both circuits? | 2-4 V | Go to Step 8 | Go to Step 9 |
| 8 | - Turn OFF the ignition.
- Connect a test lamp between the TAC motor control 1 and TAC motor control 2 circuit of the throttle body harness connector.
- Turn ON the ignition for about 5 seconds and then turn OFF the ignition while you observe the test lamp. Repeat this procedure, as necessary.
Does the test lamp turn ON and then OFF each time the ignition is cycled? | - | Go to Step 12 | Go to Step 11 |
| 9 | Is the voltage less than the specified value? | 2 V | Go to Step 10 | Go to Step 14 |
| 10 | Test the TAC motor control circuit that measured below the specified value for an open or a short to ground. Did you find and correct the condition? | - | Go to Step 18 | Go to Step 13 |
| 11 | - Turn OFF the ignition.
- Disconnect the ECM.
- Test for continuity between the TAC motor control 1 and TAC motor control 2 circuit of the throttle body harness connector.
Is there continuity? | - | Go to Step 15 | Go to Step 13 |
| 12 | Test for shorted terminals and for poor connections at the throttle body connector. Did you find and correct the condition? | - | Go to Step 18 | Go to Step 16 |
| 13 | Test for shorted terminals and for poor connections at the ECM. Did you find and correct the condition? | - | Go to Step 18 | Go to Step 17 |
| 14 | Repair the appropriate TAC motor control circuit for a short to voltage. Did you complete the repair? | - | Go to Step 18 | - |
| 14 | Repair the short between the TAC motor control circuits 1 and 2. Did you complete the repair? | - | Go to Step 18 | - |
| 15 | Repair the short between the TAC motor control circuits 1 and 2. Did you complete the repair? | - | Go to Step 18 | - |
| 16 | Replace the throttle body assembly. Did you complete the replacement? | - | Go to Step 18 | - |
| 17 | Replace the ECM. Did you complete the replacement? | - | Go to Step 18 | - |
| 18 | - Clear the DTCs with a scan tool.
- Turn OFF the ignition for 30 seconds.
- Start the engine.
- Operate the vehicle within the Conditions for Setting the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records.
Did the DTC fail this ignition? | - | Go to Step 2 | Go to Step 19 |
| 19 | Check if any additional DTCs are set. Are there any DTCs that have not been diagnosed? | - | Go to applicable DTC table | System OK |
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