Where is the sensor 1 bank 1 located in 2002 Lexus Rx 300 and how to replace it?

In a 2002 Lexus RX 300, Sensor 1 Bank 1 refers to the upstream oxygen sensor located on the driver's side of the vehicle, before the catalytic converter. To replace it, first, ensure the engine is cool and disconnect the negative battery terminal. Then, locate the sensor, unplug the electrical connector, and use an oxygen sensor socket or wrench to unscrew it from the exhaust pipe. Install the new sensor by reversing these steps, ensuring it's securely tightened and the connector is reattached.