GM Service Manual Online
For 1990-2009 cars only

Diagnostic Instructions

    • Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
    • Review Strategy Based Diagnosis for an overview of the diagnostic approach.
    •  Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptor

DTC P2176: Minimum Throttle Position Not Learned

Circuit/System Description

The engine control module (ECM) controls the throttle valve by applying a varying voltage to the throttle actuator control (TAC) motor. The ECM monitors the actual throttle valve position using throttle position (TP) sensor 1 and 2.

Conditions for Running the DTC

    • The engine speed is greater than 250 RPM.
    • The vehicle speed is 0 km/h (0 mph).
    • The engine coolant temperature (ECT) is between 5-101°C (41-212°F).
    • The intake air temperature (IAT) is less than 5°C (41°F).
    • The accelerator pedal position (APP) sensor angle is greater than 14 percent.
    • The ignition 1 voltage is greater than 10 volts.
    • DTC P2176 runs continuously once the above conditions are met for greater than 1 second.

Conditions for Setting the DTC

    • The ECM detects that the TP sensor 1 voltage is not between 0.2-0.9 volt during the throttle learn procedure.
    • The ECM detects that the TP sensor 2 voltage is not between 4.1-4.8 volts during the throttle learn procedure.
    • The minimum throttle position is not learned after an ECM replacement.
    • Any of the above conditions exist for greater than 4 seconds.

Action Taken When the DTC Sets

DTC P2176 is a Type A DTC.

Conditions for Clearing the DTC

DTC P2176 is a Type A DTC.

Circuit/System Verification

  1. Ignition ON, rapidly depress the accelerator pedal from the rest position to the wide open throttle position (WOT) and release the pedal. Repeat the procedure several times. Observe the scan tool DTC information parameter. DTCs P0121, P0122, P0123, P0221, P0222, P0223, or P0638 should not set.
  2. If any DTCs are set, refer to Diagnostic Trouble Code (DTC) List - Vehicle DTC P0121, P0122, P0123, P0221, P0222, P0223, or P2135 for further diagnosis.
  3. DTC P2176 is an informational DTC. Perform the idle learn procedure.
  4. If DTC P2176 resets after performing the idle learn procedure, replace the throttle body.
  5. 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.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    •  Throttle Body Assembly Replacement
    •  Control Module References for engine control module replacement, setup, and programming