There are 2 bank of o2 sensors on Toyota Avalons. Bank1 sensors are on the exhaust piping. Sensor 1 is BEFORE the catalytic converter and is the one you need to look at. Although it is possible it just needs a good cleaning, it is easy to replace. A 22mm metric wrench and some anti-seize will do it.
Repair the problem that turned it on and then clear the code with an OBD2 scanner/code reader
Trouble code P0741 means:Torque converter clutch circuit performance or stuck off
OBD1
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96 and up for obd2
You need an OBD2 code reader to check the codes. Just plug it in under the hood and read the codes. Use the manual to determine the codes.
The ECU has detected a problem with the emissions system. Have the ECU scanned with an OBD2 scan tool to retrieve the code that has been set. This code will tell you where to start looking for the problem.
Open the flap under the steering wheel, and you can see the 18 pin socket. Plug your OBD2 device here. However, be aware that TOYOTA uses a different protocol as I could not get to work with my OBD2 device.
Plug in an OBD2 code reader. You can borrow, rent or purchase an OBD2 code scanner at most auto parts retailers.
The obd2 plug is under the knee board (under the column).
Yes, it is called the OBD2 code list.
There is no OBD2 connector on a 1994 Honda Accord. Your car is not OBD2 compliant. You car is OBD1. Click the link for detailed instructions with photos on how to retrieve the code.