DTC P1516, P2101, P2119, or P2176
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
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
| P1516, P2101, P2176
| P1516, P2101, P2176
|
TAC Motor Control Open
| P1516, P2101, P2119, P2176
| P1516, P2101, P2176
| P1516, P2101, P2176
| P1516, P2101, P2176
| P1516, P2101, P2176
|
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
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
| • | 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. |
| • | 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 (TP) 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. |
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
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Scan Tool Reference
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.
- Ignition ON, observe the DTC information with a scan tool. DTC P0121, P0122, P0123, P0222, P0223, P0562, P0621, P0622, or P2135 should not set.
- Clear the DTCs with a scan tool. Ignition OFF and all vehicle systems OFF. It may take up to 2 minutes for all vehicle systems to power down.
- Ignition ON, observe the scan tool TAC Motor parameter. The reading should display Enabled.
- 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.
- Perform the scan tool 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 TAC motor control circuits are not shorted to B+.
| ⇒ | If not the specified value, replace the throttle body assembly. |
- 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.
- Ignition OFF, verify the following conditions do not exist with the Q38 throttle body assembly:
| • | 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 |
| ⇒ | If a condition is found, replace the Q38 throttle body assembly. |
Note: Disconnecting the throttle body harness connector may cause additional DTCs to set.
- Ignition OFF, disconnect the harness connector at the Q38 throttle body assembly.
- Ignition ON, verify that a test lamp does not illuminate between each motor control circuit listed below and ground.
| • | TAC Motor Control Closed circuit terminal A |
| • | TAC Motor Control Open circuit terminal B |
| ⇒ | If test lamp illuminates, test the motor control circuit for a short to voltage. If the circuit tests normal, replace the K20 ECM. |
- Ignition ON, verify that a test lamp does not illuminate between each motor control circuit listed below and B+.
| • | TAC Motor Control Closed circuit terminal A |
| • | TAC Motor Control Open circuit terminal B |
| ⇒ | If the test lamp illuminates, test the motor control circuit for a short to ground. If the circuit tests normal, replace the K20 ECM. |
- 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.
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. |
- 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+.
| • | TAC Motor Control Closed circuit terminal A |
| • | TAC 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 ECM. |
- If all circuits and connections test normal, replace the Q38 throttle body assembly.
Repair Instructions
Perform the Diagnostic Repair Verification after completing the repair.
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