Turbocharger Learn: Notes

The engine control module (ECM) performs the turbocharger (TC) learn procedure automatically when the engine coolant temperature (ECT) is least 72°C (162°F). After each ignition cycle, and before the enable criteria have been met, the ECM will use the previously learned value. If the ECM does not have a previously learned value, it will default to a stored calibrated value. The ECM will use this value until the enable criteria have been met. It will then perform this procedure to learn the new value. If the ECM attempts to perform the TC Learn procedure and fails, DTC P003A, P2598 or P2599 may set.

If a TC Learn is not performed after a related turbocharger repair, the ECM will use a stored vane position value that may be invalid. The ECM may then cause a diagnostic to fail and set an invalid DTC. Certain enable criteria must be met for the ECM to perform this procedure.

The turbocharger learn procedure is required when any of the following service procedures have been performed:

• Turbocharger vane position control solenoid valve replacement
• Turbocharger vane position sensor replacement
• ECM replacement
• Turbocharger replacement
• Any service that disturbs the turbocharger components