DTC B1221/21: Driver Door Power Window Switch Circuit Malfunction: DTC Detecting Condition
WARNING: This page is about a different car, the 2002 Toyota Avalon. However, it is still accessible from the selected car via links, so may be relevant.
DTC B1221/21 is used to notify technician how switch works. If DTC B1221/21 is not set when any power window switch on driver door is operated, switch contacts are faulty. If DTC B1221/21 is set when any power window switch on driver door is not operated, switch is stuck.