P2101

Wiring Diagram:

Throttle Actuator Control (TAC) Motor Position Performance:

P2101 - THROTTLE ACTUATOR CONTROL (TAC) MOTOR POSITION PERFORMANCE
The throttle actuator control (TAC) module contains a direct current actuator motor controlled by the ECM used to move the throttle plate (in either direction) and two throttle position sensors to determine throttle plate position. The throttle plate is held at a 7% rest position to a mechanical stop by a constant force return spring. This spring will hold the throttle plate to the stop when there is no current flowing to the actuator motor. There is another return spring, which creates constant force on the throttle plate only when the throttle plate is moved towards the full closed position. The ECM will monitor both the actuator motor and TP sensors for circuit faults as well as check to make sure both springs can return the throttle to the 7% position no matter where the throttle plate remains. DTC P2101 will set if the commanded throttle plate position (based on the actuator motor pulse width) differs greater than a calibrated amount from the actual throttle plate position (based on the TP sensors) for a certain length of time; OR if a throttle actuator motor circuit fault occurs.

DTC PARAMETERS
DTC P2101 will set if the commanded throttle plate position (based on the actuator motor pulse width) differs greater than a calibrated amount from the actual throttle plate position (based on the TP sensors);
OR
If an throttle actuator motor circuit fault occurs when:
^ Condition exists for longer than 0.5 seconds

DTC P2101 diagnostic runs continuously with ignition On. P2101 is a type A DTC

NOTE: The MIL will only illuminate if the fault is present for longer than 5 seconds.

DIAGNOSTIC AIDS

IMPORTANT: If any TP sensor 1 or 2 DTC is set, diagnose that DTCs first.

A short to ground or voltage on circuit 581 or 582 will set P0638 and P2101. An open in either, will set P2101.

If DTC P2101 is set, the ECM will default to one of the two limp home modes (random injector disable with engine speed limited to 1800 rpm). The REDUCED POWER telltale will be illuminated and the ECM will remain in this condition for the entire ignition cycle even if the fault is corrected.

To locate an intermittent problem use Scan tool to monitor DTC P2101 LAST TEST with engine running while accelerating the engine up and down the RPM band. Watching for a change from PASSED to FAILED indicates a circuit fault or throttle plate restriction is occurring.