[brifro]

2010 RAV4 base model, 4 cylinder, made in Japan. This code comes up after the skid light and check engine light came on, and the cruise control stopped working. They come back on after disconnecting the battery to clear them. I've read the posts on this site and I've watched videos, but finding the exact location of this sensor has eluded me. It's not by the driver's right lower leg, where a video showed it is for an '07 V6 . I haven't jacked it up yet but crawling underneath, I cannot see the sensor anywhere beyond the catalytic converter, so it must be in front of it. Does anybody know where it is and how to access it? I bought the part, Denso 234-4266, which the Amazon website says "will not fit" this vehicle. Help!

 

[RAVN4RED]

Bank One, Sensor 2...Can be found in the Service Manual:

http://www.rav4world.com/forums/96-4-3-general/176457-service-manuals-available-downloading.html

It runs under the radiator hose over to underside of heat shield:

Welcome to the forum!

 

[brifro]

I've read that in the 4 cylinder, sensor 2 is downstream from the catalytic converter. The diagram shows it under the hood. That actually looks more like sensor 1, which is visible under the hood behind the heat shield. Can you explain? It seems like a typo.

 

[brifro]

If that is sensor 2, then the diagram has it switched: the sensor behind the heat shield is on the left, and the plug is to the right. The diagram shows the opposite.

 

[brifro]

I also think I read somewhere that the plug for sensor 2 is accessible through a panel in the back seat. That would not be consistent with the diagram either. I sure hope someone can clarify this!

 

[RAVN4RED]

Well, the Service Manual clearly shows the sensor being installed in the exhaust pipe under the heat shield. The overview diagram above does appear to have it reversed. Haven't had to work on it myself, just referencing the manual.

 

[brifro]

I appreciate it. Can you tell me where sensor 1 is? I can't imagine it's further upstream from the one we're talking about because it seems that's as far forward as one can get in the exhaust system. And what about the seemingly universal opinion that sensor 2 is downstream from the catalytic converter? This still isn't making sense to me. Thanks.

 

[RAVN4RED]

Sensor 1 is the A-F Ratio sensor, and yes, upstream. In diagrams, it appears fairly close to sensor 2, which is just beyond one of the first TWC. But haven't had the heat shields off, so not sure exactly how far to sensor 2. Like I said, I haven't worked on it, just looking at the book. And so far, there haven't been a heck of a lot of posts from the 2AR-FE owners (4 cyl 2009 and above) about sensor problems.

Here's a link to another doc that shows more: Scroll down and check pages 52-55.

https://www.rav4world.com/d1/attachments/pdf/2009/2009_RAV4_New_Features.pdf

###

 

[brifro]

I think I've pieced it together. On page 55, the same part is identified as both the Heated Oxygen Sensor (bank 1, sensor 2) (top picture) and the Air-fuel Ratio Sensor (bank 1, sensor 1) (lower left picture). Both part names point to the exact same part. The diagram on page 54 indicates there are 2 TWC's, and that the Heated Oxygen Sensor, bank 1, sensor 2, is in-between the 2 of them, not downstream from both. Now I know I have to look forward or upstream from the second catalytic converter. A guy at Auto Zone opened a service manual, which also failed to show an accurate photo of said sensor in a 2010. So I still haven't been able to find the location, but your document gave me the lead I needed to not give in and take it to the dealer, so thanks!

 

[RAVN4RED]

You're right the service manual is lame, seem to have mixed up some info. Here's another clue, which I *think* is from below with the under-shield removed(?)

BTW, reading the many posts on the 2AZ engine (4 cyl 2008 and below), there are many instances when it turned out to be the A-F sensor. So might wanna test beforehand.

Good luck on your quest, and I hope you can post (photo appreciated) of your fix.

 

[brifro]

Every diagram I've seen here is incorrect. Getting the car up on ramps to look from below made it easy. The sensor was past the first catalytic converter, which is essentially under the hood right past the exhaust manifold, but in front of the second catalytic converter. So the pervasive advice that it is "downstream from the catalytic converter" should be clarified because it's actually down from one, up from the other. Also, the factory original was NOT a Denso (I've seen many comments stating they always are Denso), even though mine was built in Japan. It was an NTK, but also had "Toyota" on it, and a Toyota part number, which cross-referenced to the Denso number (234-4622). It also looked slightly different and had different color wiring. The wiring does not run through the body and plug in on the interior, like it does on the 2007 V6. The check engine light and skid lights are now off, and the cruise control works again, so it seems to have done the trick. Thanks for all the input. There wasn't enough room or clearance to take any helpful photos.

 

[[email protected]]

Every diagram I've seen here is incorrect. Getting the car up on ramps to look from below made it easy. The sensor was past the first catalytic converter, which is essentially under the hood right past the exhaust manifold, but in front of the second catalytic converter. So the pervasive advice that it is "downstream from the catalytic converter" should be clarified because it's actually down from one, up from the other. Also, the factory original was NOT a Denso (I've seen many comments stating they always are Denso), even though mine was built in Japan. It was an NTK, but also had "Toyota" on it, and a Toyota part number, which cross-referenced to the Denso number (234-4622). It also looked slightly different and had different color wiring. The wiring does not run through the body and plug in on the interior, like it does on the 2007 V6. The check engine light and skid lights are now off, and the cruise control works again, so it seems to have done the trick. Thanks for all the input. There wasn't enough room or clearance to take any helpful photos.

Thanks for the help finding the right spot and part number for Bank1 Sensor 2 code. I have 2011 Rav4 2.5ltr and it took about 20 mins to change with 22mm box wrench. I made sure I put some anti seize grease on the new 02 sensor

 

[rav4system]

Every diagram I've seen here is incorrect. Getting the car up on ramps to look from below made it easy. The sensor was past the first catalytic converter, which is essentially under the hood right past the exhaust manifold, but in front of the second catalytic converter. So the pervasive advice that it is "downstream from the catalytic converter" should be clarified because it's actually down from one, up from the other. Also, the factory original was NOT a Denso (I've seen many comments stating they always are Denso), even though mine was built in Japan. It was an NTK, but also had "Toyota" on it, and a Toyota part number, which cross-referenced to the Denso number (234-4622). It also looked slightly different and had different color wiring. The wiring does not run through the body and plug in on the interior, like it does on the 2007 V6. The check engine light and skid lights are now off, and the cruise control works again, so it seems to have done the trick. Thanks for all the input. There wasn't enough room or clearance to take any helpful photos.

Do yourself a favor and don't reference a v6 for engine, transmission or exhaust repairs since the v6 is gonna be a lot different than your 4 banger...