The throttle actuator control (TAC) system uses vehicle electronics and components to calculate and control the position of the throttle plate. In order to decrease idle speed the TAC system closes the throttle plate reducing airflow into the engine. In order to increase idle speed the TAC system opens the throttle plate allowing more airflow into the engine. If the actual idle RPM does not match the desired idle RPM within a calibrated time, this DTC sets.
• | DTCs P0107, P0108, P0112, P0113, P0117, P0118, P0120, P0125, P0171, P0172, P0200, P0220, P0300, P0336, P0401, P0404, P0405, P0442, P0446, P0452, P0453, P0641, P0651, P1514, P1515, P1516, P2135 are not set. |
• | The engine is operating for at least 2 seconds. |
• | The engine coolant temperature (ECT) is more than -40°C (-40°F). |
• | The intake air temperature (IAT) is more than -40°C (-40°F). |
• | The barometric pressure (BARO) is more than 65 kPa. |
• | The system voltage is between 9-18 volts. |
• | The vehicle speed is less than 4.8 km/h (3 mph). |
• | The actual idle speed is approximately 150 RPM lower than or 100 RPM more than the desired idle speed. |
• | The above condition is present for 15 seconds. |
• | The PCM will illuminate the malfunction indicator lamp (MIL) during the second consecutive trip in which the diagnostic test has been run and failed. |
• | The PCM will store conditions which were present when the DTC set as Freeze Frame/Failure Records data. |
• | The PCM will turn OFF the malfunction indicator lamp (MIL) during the third consecutive trip in which the diagnostic has run and passed. |
• | The history DTC will clear after 40 consecutive warm-up cycles have occurred without a malfunction. |
• | The DTC can be cleared by using a scan tool. |
If the condition is intermittent, refer to Intermittent Conditions .
The number below refers to the step number on the diagnostic table.
Step | Action | Yes | No | ||||||
---|---|---|---|---|---|---|---|---|---|
Schematic Reference: Engine Controls Schematics Connector End View Reference: Powertrain Control Module Connector End Views or Engine Controls Connector End Views | |||||||||
1 | Did you perform the Diagnostic System Check-Engine Controls? | Go to Step 2 | |||||||
Does the engine speed correspond, within 100 RPM, with each command? | Go to Diagnostic Aids | Go to Step 3 | |||||||
3 | Is the engine RPM 100 RPM more than the desired RPM? | Go to Step 4 | Go to Step 5 | ||||||
4 | Inspect for the following conditions:
Did you complete the repair? | Go to Step 6 | -- | ||||||
5 | Inspect for energy draining load on the engine, such as ones caused by transmission conditions. Did you find and correct the condition? | Go to Step 6 | -- | ||||||
6 |
Did the DTC fail this ignition? | Go to Step 2 | Go to Step 7 | ||||||
7 | Observe the Capture Info with a scan tool. Are there any DTCs that have not been diagnosed? | System OK |