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DTC P1516, P2101, P2119, or P2176

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

DTC P2101: Throttle Actuator Position Performance

DTC P2119: Throttle Closed Position Performance

DTC P2176: Minimum Throttle Position Not Learned

Diagnostic Fault Information

Circuit

Short to Ground

High Resistance

Open

Short to Voltage

Signal Performance

TAC Motor Control Closed

P1516, P2101, P2176

P1516, P2101, P2176

P1516, P2101, P2176

P0690, P1516, P2101, P2176

P1516, P2101, P2176

TAC Motor Control Open

P1516, P2101, P2119, P2176

P1516, P2101, P2176

P1516, P2101, P2176

P0690, P1516, P2101, P2176

P1516, P2101, P2176

Circuit/System Description

The throttle body assembly contains a contact-less inductive throttle position sensing element that is managed by a customized integrated circuit. The throttle position sensor is mounted within the throttle body assembly and is not serviceable. The engine control module (ECM) supplies the throttle body with a 5 V reference circuit, a low reference circuit, an H-bridge motor directional control circuit, and an asynchronous signal/serial data circuit. The asynchronous signal means communication is only going from the throttle body to the ECM. The throttle body cannot receive data from the ECM over the signal/serial data circuit. The throttle position sensor provides a signal voltage that changes relative to throttle blade angle. The customized integrated circuit translates the voltage based position information into serial data using the Society of Automotive Engineers (SAE) J2716 Single Edge Nibble Transmission (SENT) protocol. The throttle position sensor information is transmitted between the throttle body and the ECM on the signal/serial data circuit. The ECM decodes the serial data signal and is used as voltages for throttle position sensor 1 and 2.

The 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 sensor signal/serial data circuit to determine the actual throttle valve position.

Conditions for Running the DTC

P1516

    • The run/crank or powertrain relay voltage is greater than 6.4 V and reduced power is not active.
    • DTC P1516 runs continuously when the above conditions are met.

P2101

    • DTC P1682 is not set.
    • The run/crank or powertrain relay voltage is greater than 6.4 V and reduced power is not active.
    • The engine is running or the following conditions are met:
       - The engine is not running.
       - The ignition voltage is greater than 11 V.
       - The TAC system is not in the Battery Saver mode.
       - The ECM is commanding the throttle.
       - The ECM has learned the minimum throttle position.
    • DTC P2101 runs continuously when the above conditions are met.

P2119

    • DTCs P0122, P0123, P0222, P0223, or P06A3 is not set.
    • The run/crank or powertrain relay voltage is greater than 6.4 V and reduced power is not active.
    • The system is not in the Battery Save mode.
    • The ECM is not commanding the throttle.
    • DTC P2119 runs continuously when the above conditions are met.

P2176

    • The run/crank or powertrain relay voltage is greater than 6.4 V and reduced power is not active.
    • DTC P2176 runs continuously when the above conditions are met.

Conditions for Setting the DTC

P1516

The ECM detects an unstable throttle position for greater than 1 s.

P2101

    •  The ECM detects the actual throttle position does not match the predicted throttle position for greater than 1 s.
        Or
    • The ECM detects the throttle control is driving the throttle in the incorrect direction or exceed the reduced power limit.

P2119

The ECM determines that the throttle blade did not return to the rest position within 1 s.

P2176

The ECM detects that both throttle position sensors were greater than a predetermined voltage during the minimum throttle learn procedure for greater than 2 s.

Action Taken When the DTC Sets
    • DTCs P1516, P2101, and P2176 are type A DTCs.
    • DTC P2119 is a type C DTC.
    • The ECM 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
    • DTCs P1516, P2101, and P2176 are type A DTCs.
    • DTC P2119 is a type C 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.
    • A high resistance condition on the throttle position and throttle actuator control circuits could cause a DTC to set.
    • A low battery condition may cause a DTC to set.

Reference Information

Schematic Reference

Engine Controls Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Throttle Actuator Control (TAC) System Description

Electrical Information Reference

    •  Circuit Testing
    •  Connector Repairs
    •  Testing for Intermittent Conditions and Poor Connections
    •  Wiring Repairs

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification
  1. Ignition ON.

    2. Note: A low battery voltage or charging system condition may cause a DTC to set.

  2. Verify DTC P0121, P0122, P0123, P0222, P0223, P0562, P0621, P0622, or P2135 is not set.
    3. [ARW-LISTFAIL]

  3. If any of the DTCs are set

    Refer to Diagnostic Trouble Code (DTC) List - Vehicle for further diagnosis.

    4. [/ARW-LISTFAIL][ARW-LISTPASS]

  4. If none of the DTCs are set

    5. [/ARW-LISTPASS]
  5. Verify the scan tool Throttle Body Idle Airflow Compensation parameter is less than 90 %.
    6. [ARW-LISTFAIL]

  6. 90 % or greater

    Refer to Throttle Body Cleaning .

    7. [/ARW-LISTFAIL][ARW-LISTPASS]

  7. If less than 90 %

    8. [/ARW-LISTPASS]
  8. Clear the DTCs with a scan tool.
  9. Ignition OFF and all vehicle systems OFF. It may take up to 2 minutes for all vehicle systems to power down.
  10. Ignition ON.
  11. Verify the scan tool TAC Motor parameter displays Enabled.
    12. [ARW-LISTFAIL]

  12. If Disabled

    Refer to Circuit/System Testing

    13. [/ARW-LISTFAIL][ARW-LISTPASS]

  13. If Enabled

    14. [/ARW-LISTPASS]
  14. Verify DTC P1516, P2101, P2119, or P2176 is not set.
    15. [ARW-LISTFAIL]

  15. If any of the DTCs are set

    Refer to Circuit/System Testing

    16. [/ARW-LISTFAIL][ARW-LISTPASS]

  16. If none of the DTCs are set

    17. [/ARW-LISTPASS]

    Note: If there is a condition with the throttle body, the TAC Motor Command parameter will go to 99 % for a predetermined amount of time and then a DTC sets. Once a DTC is set, the TAC Motor Command parameter will go to 0 % and the TAC Motor parameter will display Disabled.

  17. Verify the scan tool TAC Motor parameter displays Enabled while performing the Throttle Sweep Test with a scan tool.
    18. [ARW-LISTFAIL]

  18. If Disabled

    Note: Before replacing the throttle body assembly, make sure the TAC motor control circuits are not shorted to B+.

    Test or replace the Q38 throttle body assembly.

    19. [/ARW-LISTFAIL][ARW-LISTPASS]

  19. If Enabled

    20. [/ARW-LISTPASS]
  20. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.
  21. Verify a DTC does not set.
    22. [ARW-LISTFAIL]

  22. If any DTC sets

    Refer to Diagnostic Trouble Code (DTC) List - Vehicle for further diagnosis.

    23. [/ARW-LISTFAIL][ARW-LISTPASS]

  23. If no DTCs set

    24. [/ARW-LISTPASS]
  24. All OK

Circuit/System Testing
  1. Ignition OFF.

    2. Warning: Turn OFF the ignition before inserting fingers into the throttle bore. Unexpected movement of the throttle blade could cause personal injury.

  2. Verify the conditions listed below do not exist with the Q38 throttle body assembly:
    3. • A throttle blade that is not in the rest position
    • A throttle blade that is binding open or closed
    • A throttle blade that is free to move open or closed without spring pressure
    [ARW-LISTFAIL]

  3. If a condition is found

    Test or replace the Q38 throttle body assembly.

    4. [/ARW-LISTFAIL][ARW-LISTPASS]

  4. If a condition is not found

    5. [/ARW-LISTPASS]
  5. Ignition OFF.

    6. Note: Disconnecting the throttle body harness connector may cause additional DTCs to set.

  6. Disconnect the harness connector at the Q38 throttle body assembly, ignition ON.
  7. Verify that a test lamp does not illuminate between each motor control circuit listed below and ground.
    8. • TAC Motor Control Open circuit terminal 1
    • TAC Motor Control Closed circuit terminal 2
    [ARW-LISTFAIL]

  8. If the test lamp illuminates

    9. [/ARW-LISTFAIL]
    5.1. Ignition OFF, disconnect the harness connector at the K20 engine control module, ignition ON
    5.2. Test for less than 1 V between the control circuit and ground.
    [ARW-LISTFAIL]

  9. If 1 V or greater, repair the short to voltage on the circuit.

    10. [/ARW-LISTFAIL] [ARW-LISTPASS]

  10. If the test lamp is always OFF

    11. [/ARW-LISTPASS]
  11. Verify that a test lamp does not illuminate between each motor control circuit listed below and B+.
    12. • TAC Motor Control Open circuit terminal 1
    • TAC Motor Control Closed circuit terminal 2
    [ARW-LISTFAIL]

  12. If the test lamp illuminates

    13. [/ARW-LISTFAIL]
    6.1. Ignition OFF, disconnect the harness connector at the K20 engine control module.
    6.2. Test for infinite resistance between the control circuit and ground.
    [ARW-LISTFAIL]

  13. If less than infinite resistance, repair the short to ground on the circuit.

  14. If infinite resistance, replace the K20 engine control module.

    15. [/ARW-LISTFAIL][ARW-LISTPASS]

  15. If the test lamp is always OFF

    16. [/ARW-LISTPASS]
  16. Ignition OFF, set the DMM to the 40 V scale, select the Min/Max Recording Mode, and set the Peak Min/Max response time to 1 ms.

    17. Note: 

       • The DMM Min/Max Recording Mode and the response time of 1 ms must be reset after testing each circuit.
       • The ignition must be OFF and the ECM completely powered down before testing each circuit.

  17. Verify the Max voltage is within 1 V of B+ while using DMM Min/Max Recording Mode function on each control circuit listed below as the ignition is turned ON.
    18. • TAC Motor Control Open circuit terminal 1
    • TAC Motor Control Closed circuit terminal 2
    [ARW-LISTFAIL]

  18. If not within 1 V of B+

    19. [/ARW-LISTFAIL]
    8.1. Ignition OFF, disconnect the harness connector at the K20 engine control module.
    8.2. Test for less than 2 Ω in the control circuit end to end.
    [ARW-LISTFAIL]

  19. If 2 Ω or greater, repair the open/high resistance in the circuit.

  20. If less than 2 Ω, replace the K20 engine control module.

    21. [/ARW-LISTFAIL] [ARW-LISTPASS]

  21. If within 1 V of B+

    22. [/ARW-LISTPASS]
  22. Test or replace the Q38 throttle body assembly.

Repair Instructions
    •  Throttle Body Assembly Replacement
    • Control Module References for ECM replacement, programming and setup

Repair Verification
  1. Install any components that have been removed or replaced during diagnosis.
  2. Perform any adjustments, programming or setup procedures that are required when a component is removed or replaced.
  3. Clear the DTCs with a scan tool.
  4. Ignition OFF and all vehicle systems OFF. It may take up to 2 minutes for all vehicle systems to power down.
  5. Ignition ON.
  6. Verify the scan tool TAC Motor parameter displays Enabled while performing the Throttle Sweep Test with a scan tool.
    7. [ARW-LISTFAIL]

  7. If Disabled

    Test or replace the Q38 throttle body assembly.

    8. [/ARW-LISTFAIL][ARW-LISTPASS]

  8. If Enabled

    9. [/ARW-LISTPASS]
  9. If the repair was related to a DTC, duplicate the Conditions for Running the DTC and use the Freeze Frame/Failure Records, if applicable, in order to verify the DTC does not reset.
    10. [ARW-LISTFAIL]

  10. If any DTC sets

    Refer to Diagnostic Trouble Code (DTC) List - Vehicle for further diagnosis.

    11. [/ARW-LISTFAIL][ARW-LISTPASS]

  11. If no DTCs set

    12. [/ARW-LISTPASS]
  12. All OK
   


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