P2100
DTC P0638, P2100-P2103, or P2119 (Without LF1, LFW)
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 P0638
- Throttle Actuator Control (TAC) Command Performance
DTC P2100
- Throttle Actuator Control (TAC) Motor Control Circuit
DTC P2101
- Throttle Actuator Position Performance
DTC P2102
- Throttle Actuator Control (TAC) Motor Control Circuit Low Voltage
DTC P2103
- Throttle Actuator Control (TAC) Motor Control Circuit High Voltage
DTC P2119
- Throttle Closed Position Performance
Diagnostic Fault Information
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 DTCs
P0638
* The ignition is ON or the engine is operating.
* The ignition voltage is greater than 8 V.
* The engine speed is greater than 400 rpm.
* The engine coolant temperature (ECT) is greater than 5°C (41°F).
* The intake air temperature (IAT) is 5°C (41°F).
* Throttle position adaptation is not active.
* DTCs P0638 run continuously once the above conditions are met for greater than 5 s.
P2100-P2103
* The ignition voltage is greater than 8 V.
* The ignition is ON or the engine is operating.
* DTC P2100-P2103 runs continuously once the above conditions are met.
P2119
* DTC P0111, P0112, P0113, P0116, P0117, P0118, P0119, P0700, P2122, P2123, P2127, P2128, or P2138 is not set.
* The vehicle speed is 0 km/h (0 mph).
* The engine speed is less than 250 RPM.
* The engine coolant temperature (ECT) is 5-85°C (41-185°F).
* The intake air temperature (IAT) is 5-60°C (41-140°F).
* The ignition voltage is greater than 8 V.
* The accelerator pedal position (APP) is less than 15 percent.
* DTC P2119 runs once per ignition cycle when the above conditions are met for less than 1 s.
Conditions for Setting the DTC
P0638
* The ECM detects that the commanded duty cycle for the range test high is greater than 80 percent for greater than 1 s.
OR
* The ECM detects that the commanded duty cycle for the range test low is greater than 80 percent for greater than 5 s.
P2100
The ECM detects the output circuit for the TAC motor is open, shorted to ground, or shorted to a voltage. The condition exists fro greater than 1 s.
P2101
The ECM detects a 4-50 percent difference between the commanded and the actual throttle plate position, dependant upon the rate of commanded throttle movement. The condition exists for 1 s.
P2102
The ECM detects an overheat condition with the output driver. The condition exists for 1 s.
P2103
The ECM detects an over load condition with the output driver. The condition exists for 1 s.
P2119
The ECM determines that the throttle valve did not return to the rest position within 1 s. The condition exists for greater than 1 s, or a cumulative of 10 s.
Action Taken When the DTC Sets
DTCs P0638, P2100, P2101, P2102, P2103, and P2119 are Type A DTCs.
Conditions for Clearing the DTC
DTCs P0638, P2100, P2101, P2102, P2103, and P2119 are Type A DTCs.
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 (LAU) ([1][2]Electrical Diagrams)Engine Controls Schematics (LF1) ([1][2]Electrical Diagrams)
Connector End View Reference
Component Connector End Views (Connector End Views By Name)
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 (Programming and Relearning) for scan tool information
Special Tools
* EL 34730-405 - Injector Test Lamp
* For equivalent regional tools, refer to Special Tools (Tools and Equipment).
Circuit/System Verification
1. Ignition ON, observe the DTC information with a scan tool. Verify DTC P0121, P0122, P0123, P0221, P0222, or P0223 is not set.
• If a DTC is set refer to DTC P0121-P0123 or P0221-P0223 (Without LF1, LFW) (P0121) for further diagnosis.
2. Observe the scan tool Throttle Position Sensor voltage parameters. Verify that Throttle Position Sensor 1 voltage is between 3.24-3.54 V, and Throttle Position Sensor 2 voltage is between 1.36-1.86 V.
• If either Throttle Position Sensor voltage is not within the specified range refer to DTC P0121-P0123 or P0221-P0223 (Without LF1, LFW) (P0121) for further diagnosis.
3. Rapidly depress the accelerator pedal from the rest position to the wide open throttle position (WOT) and release the pedal. Repeat the procedure several times. DTCs P0638, P2100, P2101, P2102, P2103, or P2119 should not set.
• If a DTC P0121, P0122, P0123, P0221, P0222, or P0223 set while performing this procedure refer to DTC P0121-P0123 or P0221-P0223 (Without LF1, LFW) (P0121) 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. DTC P0638, P2100, P2101, P2102, P2103, or P2119 should not set.
• If a DTC P0121, P0122, P0123, P0221, P0222, or P0223 set while performing this procedure, refer to DTC P0121-P0123 or P0221-P0223 (Without LF1, LFW) (P0121) for further diagnosis.
5. 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
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, test for 4.0-4.2 V between the TAC motor control 1 circuit terminal B and ground.
• If voltage is greater than the specified range, test each of the motor control circuits for a short to voltage. If the circuits tests normal, replace the K20 Engine Control Module.
• If voltage is less than the specified range, test the motor control 1 circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K20 Engine Control Module.
4. Connect a test lamp between the TAC motor control 2 circuit terminal A and B+. The test lamp should NOT illuminate.
• If the test lamp illuminates, test the control circuit for a short to ground. If the circuit tests normal, replace the K20 Engine Control Module.
5. Test for greater than 3.5 V between TAC motor control 1 circuit terminal B and TAC motor control 2 circuit terminal A.
• If the voltage is less than the specified value, test the motor control 2 circuit for an open/high resistance. If the circuit tests normal, replace the K20 Engine Control Module.
6. Ignition OFF, connect the EL 34730-405 - Injector Test Lamp between the TAC motor control 1 circuit terminal B and TAC motor control 2 circuit terminal A of the throttle body harness connector. Observe the injector test lamp while turning the ignition ON for 5 s and then OFF. Verify the injector test lamp illuminates brightly and then turns OFF.
• If the injector test lamp does not illuminate, replace the K20 Engine Control Module.
7. If all circuits test normal, replace the Q38 throttle body.
Repair Instructions
Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.
* Throttle Body Assembly Replacement (LF1) (Removal and Replacement)Throttle Body Assembly Replacement (LAU) (Removal and Replacement)
* Control Module References (Programming and Relearning) for Engine Control Module replacement, setup, and programming