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 2 independent signal circuits.
The TP sensors have opposite functionality. TP sensor 1 signal voltage decreases from above 4 volts at idle to below 1 volt at wide open throttle (WOT). TP sensor 2 signal voltage increases from below 1 volt at idle to above 4 volts at WOT.
If the ECM detects TP sensor 2 signal voltage is too low or too high, this DTC sets.
This diagnostic procedure supports the following DTC:
DTC P0220 Throttle Position (TP) Sensor 2 Circuit
| • | DTCs P0341, P0351, P0601, P0602, P0603, P0604, P0606, P0607 are not set. | 
| • | The ignition is ON, with the engine OFF, or the engine is operating. | 
| • | The ignition 1 voltage is more than 5.23 volts. | 
| • | DTC P0220 runs continuously when the above conditions are met. | 
| • | The ECM detects the TP sensor 2 signal voltage is less than 0.275 volt for less than 1 second. | 
| • | The ECM detects the TP sensor 2 signal voltage is more than 4.725 volts for less than 1 second. | 
| • | The control module illuminates the malfunction indicator lamp (MIL) when the diagnostic runs and fails. | 
| • | 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. | 
| • | The control module commands the TAC system to operate in the Reduced Engine Power mode. | 
| • | A message center or an indicator displays Reduced Engine Power. | 
| • | Under certain conditions the control module commands the engine OFF. | 
| • | The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail. | 
| • | A current DTC, Last Test Failed, clears when the diagnostic runs and passes. | 
| • | A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic. | 
| • | Clear the MIL and the DTC with a scan tool. | 
| • | Use the J 35616 Connector Test Adapter Kit for any test that requires probing the ECM harness connector or a component harness connector. | 
| • | 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. | 
| • | For an intermittent condition, refer to Intermittent Conditions . | 
The number below refers to the step number on the diagnostic table.
Step  | Action  | Yes  | No  | 
|---|---|---|---|
Schematic Reference: Engine Controls Schematics Connector End View Reference: Engine Control Module Connector End Views or Engine Controls Connector End Views  | |||
1  | Did you perform the Diagnostic System Check - Vehicle?  | Go to Step 2  | Go to Diagnostic System Check - Vehicle in Vehicle DTC Information  | 
Are any other DTCs set?  | Go to Diagnostic Trouble Code (DTC) List - Vehicle in Vehicle DTC Information  | Go to DTC P0121  | |