Circuit Description
During Battery Saver Mode the TAC module determines if the throttle plate is returning to the correct de-energized position. If this fault is detected the TAC module sends a message to the PCM across serial data and this DTC is set.
Conditions for Running the DTC
| • | DTC P1518 is not set. |
| • | The ignition switch is ON and the engine is off. |
| • | The ignition voltage is greater than 8.5 volts. |
| • | Battery Saver Mode is active. |
Conditions for Setting the DTC
| • | The TAC module detects that the commanded and actual throttle positions are not within a calibrated range of each other. |
| • | All above conditions met for less than 2 seconds. |
Action Taken When the DTC Sets
| • | The PCM will not illuminate the malfunction indicator lamp (MIL). |
| • | The PCM will store conditions which were present when the DTC set as Failure Records data only. This information will not be stored as Freeze Frame data. |
Conditions for Clearing the MIL/DTC
| • | A History DTC will clear after 40 consecutive warm-up cycles have occurred without a malfunction. |
| • | The DTC can be cleared by using the scan tool Clear Info function. |
Diagnostic Aids
Important: Remove any debris from the connector surfaces before servicing a component. Inspect the connector gaskets when diagnosing/replacing a component. Ensure that the gaskets are installed correctly. The gaskets prevent contaminate intrusion.
| • | If you do not find any trouble, check for mechanical problems or binding that may be temperature related. Components may not move freely in extreme heat or cold due to the presence of contaminants or ice formation. |
| • | The following may cause an intermittent: |
| - | Poor connections. Check for adequate terminal tension. Refer to Testing for Intermittent and Poor Connections for the proper procedure. |
| - | Corrosion |
| - | A mis-routed harness |
| - | A rubbed through wire insulation |
| - | Broken wire inside of the insulation |
| - | Inspect the connectors for signs of water intrusion. When this occurs, multiple DTCs should be set and no circuit or component problems can be located. |
| • | For an intermittent condition, refer to Symptoms |
| • | If a repair is completed and the DTC was cleared by using a scan tool on the same ignition cycle, the default action will not clear until an ignition cycle has occurred. |
| • | When the TAC module detects a problem within the ETC System the PCM receives a message across serial data and more than one ETC System related DTC may set. This is due to the many redundant tests run continuously on this system. Locating and repairing one individual problem may correct more than one DTC. Keep this in mind when reviewing captured DTC info. |
Test Description
The numbers below refer to the step numbers on the Diagnostic Table.
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
1 | Did you perform the Powertrain On-Board Diagnostic (OBD) System Check? | -- | ||
2 | Are any other DTCs set? | -- | Diagnose these DTCs first | |
3 |
Does the scan tool indicate throttle position within the specified range? | 10.8-23.2 % | ||
4 | Remove the throttle body/TAC assembly. Refer to Throttle Body Assembly Replacement . Did you find any obstructions preventing the throttle blade from returning to the default position? | -- | ||
5 | Remove the obstruction. Did you complete the repair? | -- | -- | |
6 | Replace the throttle body/TAC assembly. Refer to Throttle Body Assembly Replacement . Did you complete the replacement? | -- | -- | |
7 |
Does the DTC reset? | -- | ||
Does the scan tool indicate any DTCs set that you have not diagnosed? | -- | Go to the applicable DTC table | System OK |
