GM Service Manual Online
For 1990-2009 cars only

Circuit Description

The engine control module (ECM) controls the throttle valve by applying a varying voltage to the throttle actuator control motor. The ECM monitors the actual throttle valve position using throttle position (TP) sensor 1 and 2. The ECM amplifies the TP sensor 1 signal in order to obtain a more accurate signal. The ECM monitors the TP sensor 1 amplification output whenever the ignition is ON and a closed throttle test is performed. If the ECM detects the internal TP sensor 1 amplification output does not correlate with the TP sensor 1 signal voltage, this DTC sets.

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC P2107 Throttle Actuator Control (TAC) Module Internal Circuit

Conditions for Running the DTC

    • The vehicle speed is 0 km/h (0 mph).
    • The engine speed is less than 40 RPM.
    • The engine coolant temperature (ECT) is 5-85°C (41-185°F).
    • The intake air temperature (IAT) is 5-60°C (41-140°F).
    • The ignition 1 voltage is more than 10 volts.
    • The accelerator pedal position (APP) is less than 15 percent.
    • DTC P2107 runs once the above conditions are met within 6 seconds during the throttle actuator control system initialization.

Conditions for Setting the DTC

The ECM detects the internal TP sensor 1 amplification output does not correlate with the TP sensor 1 signal voltage for more than 4 seconds.

Action Taken When the DTC Sets

    • The control module stores the DTC information into memory when the diagnostic runs and fails.
    • The malfunction indicator lamp (MIL) will not illuminate.
    • The control module records the operating conditions at the time the diagnostic fails. The control module stores this information in the Failure Records.
    • The driver information center, if equipped, may display a message.

Conditions for Clearing the DTC

    • 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 non-emission related diagnostic.
    • Clear the DTC with a scan tool.

P2107

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

2

  1. Turn ON the ignition, with the engine OFF for 30 seconds.
  2. Observe the DTC information with a scan tool.

Does the scan tool display DTC P2107 failed this ignition cycle?

Go to Step 4

Go to Step 3

3

  1. Observe the Freeze Frame/Failure Records for this DTC.
  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 4

Go to Intermittent Conditions

4

Replace the engine control module (ECM). Refer to Control Module References for replacement, setup, and programming.

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