2001 Saturn L200 with electrical problems

My sister left her keys in the ignition with the power on for 11 hours and now her alternator no longer sends a signal to the battery to charge. She has replaced alternator, battery, and belt and the battery still will not charge. What else could the problem be?

If the vehicle has a 3.0L engine, alternator output won’t initiate until the engine RPM’s are at 2500 or higher.