Diagnostic Instructions

DTC Descriptors

DTC P1516: Throttle Actuator Control (TAC) Module Throttle Actuator Position Performance

DTC P2101: Throttle Actuator Position Performance

DTC P2119: Throttle Closed Position Performance

Circuit/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

DTC P1516

DTC P2101

DTC P2119

Conditions for Setting the DTC

DTC P1516

The ECM detects the difference between the actual throttle position, and the desired position is greater than 5 percent for 30 seconds.

DTC P2101

The ECM detects the difference between the actual throttle position, and the desired position is greater than 8 percent for 1.5 seconds.

DTC P2119

The ECM detects that the throttle blade did not return to the default position, during power down, within a calibrated amount of time

Action Taken When the DTC Sets

DTC P2119

DTC P2119 is a Type C DTC.

DTC P1516 or P2101

Conditions for Clearing the DTC

Diagnostic Aids

Inspect for a condition in which the throttle valve may have been held open. For example, ice may have formed in the throttle bore causing the throttle valve not to close.

Reference Information

Schematic Reference

Engine Controls Schematics

Connector End View Reference

Description and Operation

Fastener Tightening Specifications

Electrical Information Reference

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Circuit/System Verification

1. Ignition ON, using a scan tool observe the DTC information. Verify DTCs P0122, P0123, P0222, or P0223 are not set.

⇒	If any of the DTCs are set, refer to DTC P0122, P0123, P0222, P0223, or P2135 for further diagnosis.

2. Ignition ON, observe the scan tool TP Sensor percentage parameters. Verify the TP sensors are between 7-21 %.

⇒	If either TP sensor is not within the specified range, refer to DTC P0122, P0123, P0222, P0223, or P2135 for further diagnosis.

3. Rapidly depress the accelerator pedal from the rest position to the wide open throttle position (WOT) and release pedal. Repeat the procedure several times. DTCs P1516, P2101, or P2119 should not set.

⇒	If any of the DTCs P0122, P0123, P0222, P0223, or P2135 set while performing this procedure, refer to DTC P0122, P0123, P0222, P0223, or P2135 for further diagnosis.

4. Slowly depress the accelerator pedal to WOT and then slowly return the pedal to closed throttle. Repeat the procedure several times. DTCs P1516, P2101, or P2119 should not set.

⇒	If any of the DTCs P0122, P0123, P0222, P0223, or P2135 set while performing this procedure, refer to DTC P0122, P0123, P0222, P0223, or P2135 for further diagnosis.

5. If the vehicle passes the Circuit/System Verification Test, then operate the vehicle within the conditions for running the DTC. You may also operate the vehicle within the conditions that are captured in the Freeze Frame/Failure Records Data List.

Circuit/System Testing

Important: Disconnecting the throttle body harness connector causes additional DTCs to set.

1. Ignition OFF, disconnect the harness connector at the throttle body.
2. Ignition ON, measure for less than 0.5 volts on the motor control 1 and motor control 2 circuits.

⇒	If voltage is more than the specified value, test the appropriate motor control circuit for a short to voltage. If the circuit tests normal, replace the ECM.

3. Ignition OFF, probe motor control 1 and motor control 2 circuits with a test lamp connected to B+. Verify the test lamp does not illuminate.

⇒	If the test lamp illuminates, test the appropriate motor control circuit for a short to ground. If the circuit tests normal, replace the ECM.

4. Ignition OFF, connect the test lamp between the TAC motor control 1 and TAC motor control 2 circuits of the throttle body harness connector. Observe the test lamp while turning the ignition ON for 5 seconds and the OFF. Verify the test lamp illuminates.

⇒	If the test lamp does not illuminate, test each motor control circuit for an open or for a short between the TAC motor control 1 and TAC motor control 2 circuits. If the circuit tests normal, replace the ECM.

5. Inspect the throttle body for the following conditions:

•	A throttle blade that is not in the rest position

•	A throttle valve that is binding open or closed

•	A throttle valve that opens or closes without spring pressure

⇒	If a condition is found, replace the throttle body.

6. If all circuits test normal, replace the throttle body.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.