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 Descriptors
DTC P2105: Throttle Actuator Control (TAC) System - Forced Engine ShutdownCircuit/System Description
The engine control module (ECM) controls the throttle valve by applying a varying voltage to the control circuits of the throttle actuator control (TAC) motor. The ECM monitors the duty cycle that is required to actuate the throttle valve. The ECM monitors the throttle position (TP) sensors 1 and 2 to determine the actual throttle valve position.
Conditions for Running the DTC
| • | The ECM power down process in the last drive cycle completely finished. |
| • | DTC P2105 runs continuously once the above condition is met. |
Conditions for Setting the DTC
The ECM detects an incorrect voltage level at the ignition voltage supply circuits for greater than 4 seconds.
Action Taken When the DTC Sets
DTC P2105 is a Type A DTC.
Conditions for Clearing the DTC
DTC P2105 is a Type A DTC.
Diagnostic Aids
The following table illustrates the ECM connector locations:
ECM Connector Location | |
|---|---|
X2 | X1 |
Front of Vehicle | |
| • | If DTC P2105 sets, the engine will stall and not restart until the ignition is cycled OFF and then ON. |
| • | Additional DTCs set when P2105 sets. |
| • | The ignition key will not be able to be removed from the ignition switch until another ignition cycle occurs. |
Reference Information
Schematic Reference
Connector End View Reference
Description and Operation
Engine Control Module Description
Electrical Information Reference
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Scan Tool Reference
Control Module References for scan tool information
Circuit/System Verification
- Start the engine. Rapidly move the accelerator pedal from the rest position, to wide open throttle position, back to the rest position. Repeat the procedure a few times. DTC P2105 should not set.
- 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 are captured in the Freeze Frame/Failure Records Data List.
Circuit/System Testing
- Ignition OFF, remove the fuse that supplies voltage to terminals X2-1, and X2-17 of the ECM. Verify the fuse is OK.
- Install the fuse.
- Disconnect the harness connector X2 at the ECM.
- Ignition ON, load test for B+ on both ignition circuit terminals 1, and 17 at the ECM.
- If all circuits/connections test OK, replace the ECM.
Important: This DTC will only set if the fuse is open and the circuits are not grounded. The ignition voltage circuits must be tested thoroughly for an intermittent short to ground.
| ⇒ | If the fuse is open, test the ignition voltage circuit between the open fuse and the ECM for an intermittent short to ground. |
| ⇒ | If less than B+, repair the ignition circuit for an open/high resistance. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
Control Module References for engine control module replacement, setup, and programming
