GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Buick 🢒 2005 🢒 Terraza - 4WD 🢒 Brakes 🢒 Park Brake 🢒 DTC P2107

Circuit Description

The throttle actuator control (TAC) module contains data, which is essential for proper TAC system operation. The TAC module continuously tests the integrity of this data. If the TAC module detects a fault with electrically erasable programmable read only memory (EEPROM), the TAC module detects a low voltage while the voltage on the powertrain control module (PCM) is not low, or the TAC module detects the vehicle ID from TAC module does not agree with the vehicle ID from the PCM, DTC P2107 sets.

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC P2107 Throttle Actuator Control (TAC) Module Internal Circuit

Conditions for Running the DTC
    • DTCs P0606, P2108, U0107 are not set.
    • The ignition is in the Crank or Run position.

Conditions for Setting the DTC

If the TAC module detects low voltage, a fault with the EEPROM or the vehicle ID recorded in the TAC module does not match the vehicle ID recorded in the PCM.

Action Taken When the DTC Sets
    • 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.

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.

Diagnostic Aids

If the DTC is determined to be intermittent, reviewing the Failure Records can be useful in determining when the DTC was last set.

Step

Action

Yes

No

Schematic Reference: Engine Controls Schematics

Connector End View Reference: Powertrain Control Module Connector End Views and 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

2

Is DTC 2119 also set?

Go to Diagnostic Trouble Code (DTC) List - Vehicle in Vehicle DTC Information

Go to Step 3

3
  1. Observe the Freeze Frame/Failure Records for this DTC.
  2. Turn OFF the ignition for 30 seconds.
  3. Turn ON the ignition.
  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 Diagnostic Aids

4

Replace the throttle body assembly. 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

Important: Be aware that repairing 1 individual condition may correct more than 1 DTC.

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 in Vehicle DTC Information

System OK