DTC P2100, P2101, P2108, P2119, or P2176
Diagnostic Instructions
DTC Descriptors
DTC P2100 00: Throttle Actuator Control (TAC) Motor Control Circuit
DTC P2101 00: Throttle Actuator Position Performance
DTC P2108 00: Throttle Actuator Position Performance
DTC P2119 00: Throttle Closed Position Performance
DTC P2176 00: Minimum Throttle Position Not Learned
Diagnostic Fault Information
Circuit
| Short to Ground
| High Resistance
| Open
| Short to Voltage
| Signal Performance
|
Motor Control 1
| P2101 00, P2176 00
| P2101 00, P2176 00
| P2101 00, P2176 00
| P2101 00, P2176 00
| P2101 00, P2176 00
|
Motor Control 2
| P2101 00, P2176 00
| P2101 00, P2176 00
| P2101 00, P2176 00
| P2101 00, P2176 00
| P2101 00, P2176 00
|
Circuit/System Description
The engine control module (ECM) is the control centre for the throttle body throttle actuator control (TAC) system. The ECM determines the drivers intent and then calculates the appropriate throttle response. The ECM achieves throttle positioning by providing a pulse width modulated voltage to the TAC motor. The TAC motor system uses the following circuits:
Two processors are also used to monitor the TAC motor system data. Both processors are located within the ECM. Both processors monitor each others data to verify that the indicated throttle position is correct.
Conditions for Running the DTC
P2100 00
• | The ignition is ON or the engine is operating. |
• | The ignition voltage is greater than 7 V. |
• | DTCs P210 001 run continuously once the above conditions are met for greater than 5 s. |
P2101 00, P2119 00, P2176 00
• | The ignition is ON or the engine is operating. |
• | DTC P2101 00, P2119 00, and P2176 00 runs continuously once the above conditions are met. |
P2108 00
• | DTCs P0111 00, P0112 00, P0113 00, P0117 00, P0118 00, P0119 00, P0700 00, P2122 00, P2123 00, P2127 00, P2128 00, or P2138 00 is not set. |
• | DTCs P0121 00, P0122 00, P0123 00, P0221 00, P0222 00, P0223 00, P2176 00 are not set. |
• | DTC P2176 00 run continuously when the above conditions are met. |
Conditions for Setting the DTC
P2100 00
The indicated throttle position does not match the predicted throttle position for more than 0.5 s.
P2101 00, P2108 00
The indicated throttle position does not match the predicted throttle position for more than 0.3 s.
P2119 00
The ECM determines that the throttle blade did not return to the rest position within 720 ms.
P2176 00
The difference between the predicted and the actual throttle position is more than a calibrated amount for more than 1.5 s.
Action Taken When the DTC Sets
• | DTCs P2100 00, P2101 00, P2108 00 and P2176 00 are Type A DTCs. |
• | DTC P2119 00 is a Type C DTC. |
Conditions for Clearing the DTC
• | DTCs P2100 00, P2101 00, P2108 00 and P2176 00 are Type A DTCs. |
• | DTC P2119 00 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.
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
- Ignition ON, engine OFF, use a scan tool to observe the throttle position sensor 1 indicated position. Throttle position should increase as pedal is applied and decrease as pedal is released. When no accelerator pedal activity is detected, the throttle position will return to the spring loaded default position.
- DTC P2176 is an informational DTC. Perform the throttle learn procedure, refer to Throttle/Idle Learn .
- 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.
Circuit/System Testing
- 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.
- Ignition OFF, disconnect the harness connector of the Q38 Throttle Body.
- Ignition ON, test less than 0.3 V between the Q38 Throttle Body Motor Control Circuit terminal 3 X1 and ground.
⇒ | If greater than 0.3 V, test the Q38 Throttle Body Motor Control Circuit terminal 3 X1 for a short to voltage. |
⇒ | If the circuit tests normal, replace the K20 Engine Control Module. |
- Ignition ON, test for less than 0.3 V between the Q38 Throttle Body Motor Control Circuit terminal 5 X1 and ground.
⇒ | If greater than 0.3 V, test the Q38 Throttle Body Motor Control Circuit 5 X1 for a short to voltage. |
⇒ | If the circuit tests normal, replace the Q38 Throttle Body. |
- Verify that a test lamp does not illuminate between Q38 Throttle Body Motor Control Circuit terminal 3 X1 and B+.
⇒ | If test lamp illuminates, test the Q38 Throttle Body Motor Control Circuit terminal 3 X1 for a short to ground. If the circuit tests normal, replace the K20 Engine Control Module. |
- Verify that a test lamp does not illuminate between motor control circuit terminal 5 X1 and B+.
⇒ | If test lamp illuminates, test the Q38 Throttle Body Motor Control Circuit terminal 5 X1 for a short to ground. If the circuit tests normal, replace the K20 Engine Control Module. |
- Ignition OFF for 90 s. Connect a DMM between the Q38 Throttle Body Motor Control Circuit terminal 3 X1 and ground.
Note: When measuring peak voltage, ensure that the DMM is on the proper voltage scale that the response time is set to 1 ms.
- Ignition ON, test for 4-5 V on the Q38 Throttle Body Motor Control Circuit terminal 3 X1 and ground.
⇒ | If less than the specified range, test for an open/high resistance. If the circuit tests normal, replace the K20 Engine Control Module. |
- Ignition OFF for 90 s. Connect a DMM between the motor control terminal 5 X1 circuit and ground.
- Ignition ON, test for 4-5 V on the Q38 Throttle Body Motor Control Circuit terminal 5 X1 and ground.
⇒ | If less than the specified range, test for an open/high resistance. If the circuit tests normal, replace the K20 Engine Control Module. |
- If all circuits test normal, replace the Q38 Throttle Body.
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
© Copyright Chevrolet. All rights reserved |