P1517

CIRCUIT DESCRIPTION
The Throttle Actuator Control (TAC) module contains data which is essential for proper Electronic Throttle Control (ETC) system operation. The TAC module continuously checks the integrity of this data. When the TAC module is unable to write or read data to and from Random Access Memory (RAM) or the TAC module is unable to correctly read data from the flash memory or an internal TAC module processor fault is detected. This communicated to the Powertrain Control Module (PCM) across serial data and this DTC sets.

CONDITIONS FOR RUNNING THE DTC
^ The ignition is in the crank or run position.
^ DTC P1518 is not present.

CONDITIONS FOR SETTING THE DTC
The TAC module determines that an internal data test did not pass.

ACTION TAKEN WHEN THE DTC SETS
^ The control module illuminates the Malfunction Indicator Lamp (MIL) when the diagnostic runs and fails.
^ The control module records the operating conditions at the time the diagnostic fails. The control module stores this information in the Freeze Frame/Failure Records.

CONDITIONS FOR CLEARING THE MIL/DTC
^ The control module turns OFF the Malfunction Indicator Lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
^ A current DTC "Last Test Failed" clears when the diagnostic runs and passes.
^ A history DTC clears after 40 consecutive warm-up cycles, if no failures are reponed by this or any other emission related diagnostic.
^ Use a scan tool in order to clear the MIL and the DTC.

DIAGNOSTIC AIDS

IMPORTANT: Remove any debris from the connector surfaces before servicing a component. Inspect the connector gaskets when diagnosing/replacing a component. Verify that the gaskets are installed correctly. The gaskets prevent contaminate intrusion.

TEST DESCRIPTION

Steps 1-4:

The number below refers to the step number on the diagnostic table.
4. When the TAC module detects a condition within the ETC system the PCM receives a message across serial data and more than 1 ETC system related DTC may set. This is due to the many redundant tests run continuously on this system. Locating and repairing 1 individual condition may correct more than 1 DTC. Keep this in mind when reviewing captured DTC info.