GM Service Manual Online
For 1990-2009 cars only

Circuit Description

This diagnostic monitors the throttle position (TP) sensor 2 signal. There are 2 TP sensors located on the throttle body inside of the throttle actuator control (TAC) module. All throttle control is performed by the TAC system. The TP sensors, along with the accelerator pedal position (APP) sensors and the TAC module are mandatory components of the TAC system. The TP sensors are used to determine the throttle plate angle. The TP sensor is a potentiometer whose resistance value changes along with the throttle valve position. The sensor uses a 5-volt reference supply, a low reference and a signal circuit. The TAC module the signal circuit voltage to calculate the actual throttle valve opening. The TP sensor is an integral part of the TAC module is not serviced separately. Installing a new TP sensor requires the replacement of the throttle body assembly. For additional information on the operation of the TP sensor and the TAC system refer to Throttle Actuator Control (TAC) System Description .

DTC Descriptor

This diagnostic procedure supports the following DTC:

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

Conditions for Running the DTC

    • DTC P0222 is not set.
    • DTC P0223 runs continuously once the above conditions are met.

Conditions for Setting the DTC

    • The TP sensor 2 voltage is 4.85 volts or more.
    • The above condition is present for less than 1 second.

Action Taken When the DTC Sets

    • The PCM illuminates the malfunction indicator lamp (MIL) when the diagnostic runs and fails.
    • The PCM records the operating conditions at the time the diagnostic fails. The PCM stores this information in the Freeze Frame and/or Failure Records.

Conditions for Clearing the MIL/DTC

    • The PCM turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
    • A last test failed, or current DTC, clears when the diagnostic runs and does not fail.
    • A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
    • Use a scan tool in order to clear the MIL and the DTC.

Test Description

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

  1. The Diagnostic System Check - Vehicle prompts the technician to complete some basic checks and store the Freeze Frame data on the scan tool, if applicable. This creates an electronic copy of the data taken when the fault occurred. The information is then stored in the scan tool for later reference.

  2. This step determines if a fault is present. The normal TP angle at idle is between 11-15 percent.

Step

Action

Value(s)

Yes

No

Schematic Reference: Engine Controls Schematics

Connector End View Reference: Powertrain 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

2

  1. Turn ON the ignition, leaving the engine OFF.
  2. Observe the TP sensor 2 angle with a scan tool.

Is the throttle position (TP) sensor 2 angle within the specified range?

10-20%

Go to Step 3

Go to Step 4

3

  1. Observe the Freeze Frame/Failure Records for this DTC.
  2. Clear the DTCs with a scan tool.
  3. Turn OFF the ignition for 30 seconds.
  4. Start the engine.
  5. Operate the vehicle within the Conditions for Running 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

Go to Intermittent Conditions

4

Replace the throttle body. Refer to Throttle Body Assembly Replacement .

Did you complete the replacement?

--

Go to Step 5

--

5

  1. Clear the DTCs with a scan tool.
  2. Turn OFF the ignition for 30 seconds.
  3. Start the engine.
  4. Operate the vehicle within the Conditions for Running 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 6

6

Observe the Capture Info with a scan tool.

Are there any DTCs that have not been diagnosed?

--

Go to Diagnostic Trouble Code (DTC) List - Vehicle

System OK