How do you replace water pump on Toyota Sienna 2002?

To replace the water pump on a 2002 Toyota Sienna, first, disconnect the negative battery terminal and drain the coolant. Remove the serpentine belt and any components obstructing access to the water pump, such as the timing belt cover if necessary. Unbolt the old water pump, clean the mounting surface, and install the new pump with a new gasket. Reassemble the components, refill the coolant, and check for leaks before starting the engine.