Action Taken When the DTC Sets

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DTC P1258 is a Type A DTC.
The engine will operate in the Overheated Engine Protection Operating Mode.
The engine coolant temperature indicator lamp, if equipped, will illuminate.
The driver information center (DIC), if equipped, may display a message.
If the protection mode is active and an ECT sensor DTC sets, the protection mode will activate during the next drive cycle until the ECT sensor DTC runs and passes.