P1516
DTC P1516, P2101, P2119, or P2176 (LUW)
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis Strategy Based Diagnosis for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions 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
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 sensors 1 and 2 to determine the actual throttle valve position.
Conditions for Running the DTC
P1516
* The run/crank or powertrain relay voltage is greater than 6.41 V and reduced power is not active.
* The DTC runs continuously when the above conditions are met.
P2101
* DTC P1682 is not set.
* The run/crank or powertrain relay voltage is greater than 6.41 V and reduced power is not active.
* The throttle position sensor (TPS) minimum learn is not active.
* The throttle is being controlled.
* The running or ignition voltage is greater than 11 V.
* The ignition voltage is greater than 5.5 V.
* Or
* The TPS minimum learn and reduced power are active.
* The powertrain relay voltage is greater than 6.41 V.
* The DTC runs continuously when the above conditions are met.
P2119
* DTCs P0122, P0123, P0222, P0223, or P06A3 are not set.
* The run/crank or powertrain relay voltage is greater than 6.41 V and reduced power is not active.
* The powertrain relay voltage is greater than 5.5 V.
* The DTC runs continuously when the above conditions are met.
P2176
* The run/crank or powertrain relay voltage is greater than 6.41 V and reduced power is not active.
* The DTC runs continuously when the above conditions are met for greater than 2 s.
Conditions for Setting the DTC
P1516
The ECM detects an inability to maintain a steady state throttle position.
P2101
The ECM detects the actual throttle position does not match the predicted throttle position
Or
The ECM detects the throttle control is driving the throttle in the incorrect direction or exceed the reduced power limit.
P2119
The ECM detects that the throttle is unable to return to default throttle position after de-energizing electronic throttle control motor.
P2176
The ECM detects that both throttle position sensors were greater than 0.95 V during the minimum learn procedure.
Action Taken When the DTC Sets
P1516, P2101, or P2176
* DTCs P1516, P2101, and P2176 are Type A DTCs.
* The ECM commands the TAC system to operate in a reduced engine power mode.
* A message center or an indicator displays Reduced Engine Power.
* Under certain conditions the control module commands the engine OFF.
P2119
DTC P2119 is a Type C DTC.
Conditions for Clearing the DTC
* DTCs P1516, P2101, and P2176 are Type A DTCs.
* DTC P2119 is a Type C DTC.
Diagnostic Aids
* A high resistance condition with the throttle position sensor circuits could cause DTCs P1516, P2101, P2119, or P2176 to set.
* 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 [1][2]Electrical Diagrams
Connector End View Reference
Component Connector End Views Fuel Pump and Level Sensor Assembly
Description and Operation
Throttle Actuator Control (TAC) System Description Throttle Actuator Control (TAC) System Description
Electrical Information Reference
* Circuit Testing Circuit Testing
* Connector Repairs Connector Repairs
* Testing for Intermittent Conditions and Poor Connections Testing for Intermittent Conditions and Poor Connections
* Wiring Repairs Wiring Repairs
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Scan Tool Reference
Control Module References Control Module References for scan tool information
Circuit/System Verification
Note: A low battery voltage or charging system condition may cause a DTC to set.
1. Ignition ON, observe the DTC information with a scan tool. Verify DTCs P0121, P0122, P0123, P0222, P0223 or P2135 should not set.
• If any of the DTCs are set refer to DTC P0121-P0123, P0222, P0223, or P2135 (LUW) P0121 for further diagnosis.
2. Clear the DTCs with a scan tool. Ignition OFF and all vehicle systems OFF. It may take up to 2 min for all vehicle systems to power down.
3. Ignition ON, observe the scan tool TAC Motor parameter. The reading should display Enabled.
4. Observe the DTC information with a scan tool. DTC P1516, P2101, P2119, or P2176 should not set.
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.
5. Perform the Throttle Sweep Test while observing the TAC Motor parameter with a scan tool. The TAC Motor parameter should display Enabled while the Throttle Sweep Test is in progress.
Note: Before replacing the throttle body assembly, make sure the throttle control circuits are not shorted to B+.
• If not the specified value, replace the throttle body assembly.
6. 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 you observed from the Freeze Frame/Failure Records data.
Circuit/System Testing
Warning
Turn OFF the ignition before inserting fingers into the throttle bore. Unexpected movement of the throttle blade could cause personal injury.
1. Inspect the Q38 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 Q38 Throttle Body.
Note: Disconnecting the throttle body harness connector causes additional DTCs to set.
2. Ignition OFF, disconnect the harness connector of the Q38 Throttle Body.
3. Ignition ON, verify that a test lamp does not illuminate continuously between each motor control circuit listed below and ground.
* Motor control closed circuit terminal A
* Motor control open circuit terminal B
• If the test lamp illuminates, test the control circuits for a short to voltage. If the circuit tests normal, replace the K20 Engine Control Module.
4. Ignition ON, verify that a test lamp does not illuminate between each control circuit listed below and B+.
* Motor control closed circuit terminal A
* Motor control open circuit terminal B
• If the test lamp illuminates, test the appropriate control circuit for a short to ground. If the circuit tests normal, replace the K20 Engine Control Module.
5. Ignition OFF, set the DMM to 40 V scale, select the Min/Max Recording Mode, and set the Peak Min/Max response time to 1 ms.
Note:
* The DMM Min/Max Recording Mode and the response time of 1 ms must be reset after testing each circuit or a lower voltage will be recorded.
* The ignition must be OFF and the K20 Engine Control Module completely powered down before testing each circuit or a lower voltage will be recorded.
6. Ignition OFF, measure the voltage using the DMM Min/Max Recording Mode function on each circuit listed below as the ignition is turned ON. The Max voltage should be within 1 V of B+.
* Motor control closed circuit terminal A
* Motor control open circuit terminal B
• If not within the specified range, test the circuit for an open/high resistance. If the circuit tests normal, replace the K20 Engine Control Module.
7. If all circuits and connections test normal, replace the Q38 Throttle Body.
Repair Instructions
Perform the Diagnostic Repair Verification Verification Tests after completing the repair.
* Throttle Body Assembly Replacement Removal and Replacement
* Control Module References 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. Turn OFF the ignition for 60 s.
5. Perform the Throttle Sweep Test while observing the TAC Motor parameter with a scan tool. The TAC Motor parameter should display Enabled while the Throttle Sweep Test is in progress.
• If Disabled is displayed, a condition still exists.
6. 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. If the DTC resets or another DTC is present, refer to the Diagnostic Trouble Code (DTC) List - Vehicle Diagnostic Trouble Code (DTC) List - Vehicle and perform the appropriate diagnostic procedure.