DTC Advanced Diagnostics: P2176 (1.5L Engine)
DTC P2176: Throttle Actuator Control System Idle Position Not Learned
General Description
The electronic throttle control system controls the throttle valve opening. The system includes the throttle actuator, the throttle valve, throttle position (TP) sensors A and B, the PGM-FI subrelay, the accelerator pedal position (APP) sensor A/B, and the powertrain control module (PCM). When the accelerator pedal is pressed, the APP sensor A/B detects the accelerator pedal opening value. The accelerator pedal opening value is converted to a signal in the APP sensor A/B and transmitted to the PCM to compute the target position. The PCM determines the throttle valve target position according to the signal received and operates the throttle actuator to move the throttle valve to the target position. The actual throttle valve position is determined by TP sensors A and B (installed in the throttle body). The PCM transmits a signal to the throttle actuator and moves the throttle valve to the fully closed position to register the throttle valve fully closed position after the vehicle is turned to the OFF (LOCK) mode. When the registration of the throttle valve fully closed position is not completed within a predetermined time after the vehicle is turned to the OFF (LOCK) mode, also the registered value is out of predetermined range, the PCM detects a malfunction in the electronic throttle control system and stores a DTC.
Monitor Execution, Sequence, Duration, DTC Type
| Execution | Once per driving cycle |
| Sequence | None |
| Duration | 2.0 seconds or more |
| DTC Type | One drive cycle, MIL on |
Enable Conditions
| Condition | Minimum | Maximum |
|---|---|---|
| 12 volt battery voltage [Battery] | 6.0 V | - |
| Vehicle | OFF (LOCK) mode | |
[ ]: HDS Parameter
Malfunction Threshold
One of these conditions is met, when the registration of the throttle valve fully closed position is not completed for at least 2.0 seconds after the vehicle condition is turned to the OFF (LOCK) mode:
- The registered value of the throttle valve fully closed position is more than 1.02 V, or less than 0.49 V.*
- The registered value of the throttle valve fully closed position is more than 4.51 V, or less than 3.98 V.**
*: TP sensor A [TP Sensor A]
**: TP sensor B [TP Sensor B]
Possible Cause
The causes shown may not be a complete list of all potential problems, and it is possible that there may be other causes.
- PCM internal circuit failure
- Throttle actuator MTR1 line failure
- Throttle actuator MTR2 line failure
- Throttle body internal failure
Diagnosis Details
Conditions for setting the DTC
When a malfunction is detected, the MIL comes on and a Pending DTC, a Confirmed DTC, the freeze data, and the on-board snapshot are stored in the PCM memory.
Conditions for clearing the DTC
The MIL is cleared if the malfunction does not return in three consecutive trips in which the diagnostic runs. The MIL, the Pending DTC, the Confirmed DTC, the freeze data, and the on-board snapshot can be cleared with the scan tool clear command.