Codes P0135 and P0155

bank 1 is the exhaust bank with No 1 cylinder bank 2 the other side sensor 1 is the up stream sensor that is the top sensor. i would fist check with a live data reader that the sensors are faulty first.

Here is a guide that will show what you are in for when doing the job

https://www.2carpros.com/articles/how-to-replace-an-oxygen-sensor

Please let us know what happens.

Well, I want to ask you about the two sensors, They are both giving a "heater circuit malfunction", (P0135 and P0155), so Is there something I can do to check like a fuse or anything simply because I have two codes related to the heater malfunction? I also went to the Toyota dealer to price sensors and also get the correct factory part numbers if I want to purchase them online. According to the Dealer Bank 1 Sensor 1 is the "right" side (rear exhaust manifold by the firewall) and the Bank 2 Sensor 1 is the "left" side (forward exhaust manifold near radiator). Does this make sense? I do not have a firing order diagram or cylinder number layout diagram that is why i am asking. I am sure that I will not be able to check with a live data reader although I believe my OBD2 scanner will check the 02 system and the 02 sensor icon will stop blinking after the 02 system is working. Is this what you are asking? What would cause both heater circuits to cause the codes?

I also believe that they are called air fuel ratio sensors. Right side part number 89467-41030 and left side part # 89467-41040 at Toyota dealership $276.20 each.

Hello,

Yes, heater codes are common. Replace the sensors with new and the problem should be fixed.

Please let us know what happens.

Cheers, Ken