P2100

DTC P2100

Circuit Description

The engine control module (ECM) opens the throttle blades by applying a pulse width modulated voltage to the throttle valve motor. The ECM reverses the polarity on the throttle valve motor control circuits in order to close the throttle blades. The ECM increases the pulse width as necessary to open the throttle blades. The ECM monitors the voltage on the motor control circuits. If the ECM detects the voltage on the motor control circuits are not within a predetermined value, DTC 2100 sets.

Conditions for Running the DTC

The ignition is ON.

Conditions for Setting the DTC

The ECM detects incorrect voltage on the motor control circuits.

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 MIL/DTC

^ 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.

Diagnostic Aids

^ Inspect for a condition in which the throttle valves may have been held open.
^ Inspect for conditions in which ice may have formed in the throttle bore.
^ The throttle valves are spring loaded to a slightly open position.
^ The throttle valves should not be completely closed, nor should they be open any more than the specified amount.
^ The throttle valves should move to the open and closed position without binding under the normal spring pressure.
^ The throttle should NOT be free to move open or closed WITHOUT spring pressure.
^ The scan tool has the ability to operate Throttle Control System using the Throttle Position function located in the TAC System menu. This function will operate the throttle valve through the entire range in order to determine if the throttle body and system operate correctly.
^ If the condition is intermittent, refer to Intermittent Conditions.