P0222

DTC P0121, P0122, P0123, P0221, P0222, or P0223

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle (Initial Inspection and Diagnostic Overview) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (Initial Inspection and Diagnostic Overview) for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions (Initial Inspection and Diagnostic Overview) provides an overview of each diagnostic category.



DTC Descriptors
DTC P0121
- Throttle Position (TP) Sensor 1 Performance

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

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

DTC P0221
- Throttle Position (TP) Sensor 2 Performance

DTC P0222
- Throttle Position (TP) Sensor 2 Circuit Low Voltage

DTC P0223
- Throttle Position (TP) Sensor 2 Circuit High Voltage




Diagnostic Fault Information






Typical Scan Tool Data






Circuit/System Description

The throttle body assembly contains 2 throttle position (TP) sensors. The TP sensors are mounted to the throttle body assembly and are not serviceable. The TP sensors provide a signal voltage that changes relative to throttle blade angle. The engine control module (ECM) supplies the TP sensors with a common 5-volt reference circuit , a common low reference circuit, and two independent signal circuits. The TP sensors have opposite functionality . TP sensor 1 signal voltage increases from below 1 volt at idle to above 4 volts at wide open throttle (WOT). TP sensor 2 signal voltage decreases from above 4 volts at idle to below 1 volt at WOT.


Conditions for Running the DTC


P0121
* The ignition voltage is greater than 7 volts.
* The TP sensor 1 voltage is between 0.18-4.6 volts.
* DTC P0121 runs continuously once the above conditions are met.



P0122, P0123, P0222, and P0223
* The ignition is ON, with the engine OFF, or the engine is operating.
* The ignition voltage is greater than 7 volts.
* DTC P0122 runs continuously once the above conditions are met.



P0221
* The ignition voltage is greater than 7 volts.
* The TP sensor 2 voltage is between 0.16-4.9 volts.
* DTC P0221 runs continuously once the above conditions are met.



Conditions for Setting the DTC

P0121

The TP sensor 1 disagrees greater than 6 percent from TP sensor 2 for greater than 0.14 second, and TP sensor 1 disagrees greater than 9 percent from the predicted value for greater than 0.24 second.

P0122

The ECM detects the TP sensor 1 signal voltage is less than 0.18 volt for greater than 0.14 second.

P0123

The ECM detects the TP sensor 1 signal voltage is greater than 4.6 volts for greater than 0.14 second.

P0221

The TP sensor 1 disagrees greater than 6 percent from TP sensor 2 for greater than 0.14 second, and TP sensor 2 disagrees greater than 9 percent from the predicted value for greater than 0.24 second.

P0222

The ECM detects the TP sensor 2 signal voltage is less than 0.16 volt for greater than 0.14 second.

P0223

The ECM detects the TP sensor 2 signal voltage is greater than 4.9 volts for greater than 0.14 second.


Action Taken When the DTC Sets

* DTCs P0121 and P0221 are Type B DTCs.
* DTCs P0122, P0123, P0222, and P0223 are Type A DTCs.



Conditions for Clearing the DTC

* DTCs P0121 and P0221 are Type B DTCs.
* DTCs P0122, P0123, P0222, and P0223 are Type A DTCs.



Diagnostic Aids

If there is a condition with the TP sensors the ECM defaults to reduced power mode for the entire ignition cycle, even if the condition is corrected.


Reference Information
Schematic Reference

Engine Controls Schematics (Electrical Diagrams)
Connector End View Reference

Component Connector End Views (Connector Views)
Electrical Information Reference

* Circuit Testing (Component Tests and General Diagnostics)
* Connector Repairs (Component Tests and General Diagnostics)
* Testing for Intermittent Conditions and Poor Connections (Component Tests and General Diagnostics)
* Wiring Repairs (Component Tests and General Diagnostics)

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions (Diagnostic Trouble Code Descriptions)
Scan Tool Reference

Control Module References (Programming and Relearning) for scan tool information


Circuit/System Verification

1. Ignition ON, observe the DTC information with a scan tool. DTC P0697, P0698, or P0699 should not be set.

• If a DTC is set, refer to DTC P0641, P0642, P0643, P0651, P0652, P0653, P0697, P0698 or P0699 (P0641) .

2. Clear the DTC Info with a scan tool.
3. Start the engine, observe the scan tool TP Sensor 1 and 2 voltage parameters. TP sensor 1 should be between 0.17-4.6 volts and TP sensor 2 should be between 0.15-4.8 volts.
4. Observe the scan tool TP sensor 1 and 2 parameters while performing 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.
The TP sensor 1 and 2 parameter should display Agree.

5. Observe the DTC Information with a scan tool. DTCs P0121, P0122, P0123, P0221, P0222, and P0223 should not set.
6. Operate the vehicle within the Conditions for Running the DTC to verify the DTC does not reset. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.



Circuit/System Testing

1. Ignition OFF, remove the fuse that supplies B+ to terminal X2-56 of the ECM.
2. Disconnect the throttle body harness connector.

Important: The control module or the sensor may be damaged if the circuit is shorted to battery positive voltage.


3. Test for 5 ohms or less between the low reference circuit terminal C and ground.

• If greater than the specified range, test the low reference circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the ECM.

4. Install fuse that supplies B+ to terminal X2-56 of the ECM.
5. Ignition ON, load test for 4.8-5.2 volts between the test lamp probe connected to the 5-volt reference circuit terminal E and ground.


Important: The 5-volt reference circuits are internally and externally connected at the ECM. Other component DTCs may be set. If other DTCs are set, review the electrical schematic and diagnose the applicable circuits and components.


• If less than the specified range, test the 5-volt reference circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the ECM.


• If greater than the specified range, test the 5-volt reference circuit for a short to voltage. If the circuit tests normal, replace the ECM.

6. Ignition ON, verify that the scan tool TP sensor 1 voltage parameter is less than 0.3 volt.

• If greater than the specified value, test the signal circuit for a short to voltage. If the circuit tests normal, replace the ECM.

7. Connect a 3A fused jumper wire between the 5 volt reference circuit terminal E and the TP sensor 1 signal circuit terminal D. Verify the scan tool TP sensor 1 voltage parameter is greater than 4.89 volts.

• If less than the specified value, test the signal circuit for an open/high resistance or for a short to ground. If the circuit tests normal, replace the ECM.

8. Verify the scan tool TP sensor 2 voltage parameter is greater than 4.97 volts.

• If less than the specified value, test the signal circuit for a short to ground. If the circuit tests normal, replace the ECM.


Important: If the fuse in the jumper wire opens, the signal circuit is shorted to a voltage.


9. Connect a 3A fused jumper wire between the TP sensor 2 signal circuit terminal F and the low reference circuit terminal C. Verify the TP sensor 2 voltage parameter is less than 0.10 volt.

• If greater than the specified value, test the signal circuit for an open/high resistance or for a short to voltage. If the circuit tests normal, replace the ECM.

10. If all circuits test normal, replace the throttle body assembly.



Repair Instructions

Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.

* Throttle Body Assembly Replacement (Removal and Replacement)
* Control Module References (Programming and Relearning) for engine control module replacement, setup, and programming