DTC P1526: TP Sensor Learn Not Done After Reprogramming: Description
WARNING: This page is about a different car, the 2001 Saturn LW300 and 2001 Saturn L300. However, it is still accessible from the selected car via links, so may be relevant.
Anytime a throttle body or ECM is replaced, or there is loss of battery power, ECM must relearn the throttle. Throttle is relearned when ignition is turned on (engine off) for one minute. ECM learns the throttle valve travel and records sensor readings at extreme position. DTC sets when this process did not occur after throttle body or ECM replacement, or after a loss of power. System runs in irreversible reduced power mode.