P1135 and P0125 code

[Shalina]

Hi,
My 2000 Sienna showing P1135 and P0125 code. This is for A/F Sensor1 and bank1. I am not sure exactly where it is located. I saw one near radiator and
one is near catalytic converter and one in the midle (can be seen from bottom of engine). what is OEM P/No. I need to buy. If it is bottom one, how I can replaced. Thanks in advance ..

[hsdad]

"Bank 1" is the side of the engine that houses Cylinder 1.
For me and my 2002 Sienna, that is the side of the engine OPPOSITE, away from, the radiator.

The A/F sensor no. 1 and no. 2 are both in the same basic part of the exhaust manifold for each of the three cylinders on their associated side (or bank).

The P1135 and P1155 are specific Toyota codes for the same heated air/fuel sensor but on opposite sides of the engine.

I have changed my P1155 sensor...it took about 3.5 seconds (obviously some exageration here!), my new code is P1135 since changing the front (radiator side) A/F and, as yet, I have not come up with a workable approach (and am running out of tiime on my emissions test).

hope this helps.

[liquidsilver]

For Etest, can't you just disconnect the battery (which will get rid of CEL) and go for the test? Chances are it will pass.

[hsdad]

Originally Posted by liquidsilver

For Etest, can't you just disconnect the battery (which will get rid of CEL) and go for the test? Chances are it will pass.

I'll give it a shot, and let you know.
I think these heated A/F monitoring circuits are pretty clever...in that, they just don't look at an "on or off" condition but may check themselves after a whole series of other conditions are met/satisfied.

but thanks, I'll see if the Universal battery disconnect "reset" works for P1135 and P1155 conditions.

.....

would anybody care to share how they approached a Bank 1 sensor changeout? Was part(s) removal a necessary prerequiste (Like the whole steering gear assembly?

[Nad1370]

Don't need to take the steering out. Just get under the vehicle and have either one of these -->
Apply some kind of penetrant and work the sensor back and forth if it's coming out tight. This will decrease the risk of stripping it off the manifold.

Good luck.

[05DCLB]

Bank 1 is against the firewall, sometimes A/F sensors come out, sometimes the manifold threads ball-up. Most times you can clean up manifold with a thread tap.

[deanus]

Did the problem get resolved? I'm getting codes 1135 and 1155 . I'm getting no response when I check the resistance on the heater circuit bank 1 sensor 1 (and that was difficult to get to) but I'm also getting no connection across bank 2 sensor 1 (no code showing). My voltage was the same going to each sensor so I took the chance and swapped them. I'm still getting the same codes even though I now have the "good" sensor where the "bad" sensor was located. These things are pricey. Am I missing something. Haven't done any wiring check on the post cat sensor since I guess it's plugged in under the rug or something. I've been driving a while now and don't want to end up buying a new cat.

[Qslim]

Originally Posted by deanus

Did the problem get resolved? I'm getting codes 1135 and 1155 . I'm getting no response when I check the resistance on the heater circuit bank 1 sensor 1 (and that was difficult to get to) but I'm also getting no connection across bank 2 sensor 1 (no code showing). My voltage was the same going to each sensor so I took the chance and swapped them. I'm still getting the same codes even though I now have the "good" sensor where the "bad" sensor was located. These things are pricey. Am I missing something. Haven't done any wiring check on the post cat sensor since I guess it's plugged in under the rug or something. I've been driving a while now and don't want to end up buying a new cat.

I think you are missing something here, you're testing confirmed the two codes you say you have. P1135 is a heater circuit problem on bank 1, sensor 1. P1155 is is bank 2, sensor 1.

[deanus]

Well, I see our problem. There's a code list on Toyota nation from 3/29/2006 that say's 1155 is bank 2 sensor 1 but the slip from autozone says that 1155 is bank 1 sensor 2 as do a couple of other sites I searched. But now as I search more I found another one listed your way. Could Autozones diag. tool be wrong? That would simplify this although is there something that could have caused both heater circuits to burn out, short or break simultaneously at 40k miles. A relay I can't locate perhaps. Thanks for your help.

[Qslim]

Originally Posted by deanus

Well, I see our problem. There's a code list on Toyota nation from 3/29/2006 that say's 1155 is bank 2 sensor 1 but the slip from autozone says that 1155 is bank 1 sensor 2 as do a couple of other sites I searched. But now as I search more I found another one listed your way. Could Autozones diag. tool be wrong? That would simplify this although is there something that could have caused both heater circuits to burn out, short or break simultaneously at 40k miles. A relay I can't locate perhaps. Thanks for your help.

Oddly enough, I've seen 1155 listed like this before. One way to know for sure is that you won't have a code for an air/fuel ratio sensor at the sensor 2 location, rather one for an oxygen sensor. This will be a "P0xxx" instead of "P1xxx".
Obviously you have verified that you have opens inside the sensor, so they'll both need replacing (at least by the time your emissions check is due). In my years with Toyota, I have never seen an O2 or AF code caused by anything other than sensor failures. Not to say it can't happen, it's just that factory wiring problems on yotes are extremely rare. The heater in the sensor body is basically just a filament that heats the sensor up quickly for efficient operation. Add to the fact that it hangs out in the exhaust stream all day, and a failure at that point isn't uncommon. I would bet on the fact that your case is just coincidental. Try finding a deal on a factory sensor online, you can get one much cheaper than at the parts counter. Hope this helps.

[deanus]

Thanks for your help, I'll let you know how I fair.

[hsdad]

Originally Posted by deanus

Thanks for your help, I'll let you know how I fair.

deanus,
sorry that I have been away from the board for awhile.
Let me provide an update.

Recap.
I originally coded as a P1135 (Bank 2, Sensor 1). That was happy news because that sensor can be changed without any stress with a basic 7/8 open-end wrench.

after spending 207.00 for the sensor at the Toyota Dealer (I believe a Danzo/OEM may be around 180.00), putting it in, my check engine code changed from P1135 to the 'infamous' P1155 ...the evil back side/Bank 1 (Bank 1 relates to the side with cylinder no.1).

For me to succeed in getting the wiring connector disconnected and removing the sensor I ended up removing the passenger side front tire/wheel AND removing the Tie Rod End to allow me to move the tie rod out of the way so that my arm could reach into the space to release the connector and operate a standard open-end wrench.
Note: there may be contortionists with little spaghetti arms that could do this without removal of the tie rod end but I am not one of them. Also, I studied the connector operation on the side I could easily approach to gain confidence of how to operate this 'by feel' at the end of my right-arm's reach (unless you are a masochist, a 'cool' exhaust pipe is a must ).

I used a VOM set to read resistance measurement (ohms) and checked the resistance across the two pins that are connected to the sensor by black wires (this is the heater element portion of this 4-wire sensor). Sure enough, the reading indicated an 'open' circuit ---very high resistance in the Megohm range of digital meter.

the new sensor AND the one I removed from the Bank 2 side, both read somewhere around (or below) 20 ohms (it's been awhile, sorry for not having the exact value). I regret not being as confident and well-informed to qualify a living or dead sensor before I changed out the front/Bank 2 sensor but silly me...I trusted a specific code.

I put my recently removed sensor from Bank 2, back into the Bank 1 location, and then ran the car. IT TOOK MUCH LONGER THAN I ORIGINALLY THOUGHT IT WOULD for the check engine light to clear.....but it did clear (somewhere between 10-50 miles of driving consistently 50 mph or greater).

the good news...
I compared the two sensors for physical attributes, they are virtually identical with the exception of a slight difference in the length of the wiring between the sensor and the connector. I think the bank 2 (front/radiator side sensor) had a slightly longer pigtail then the Bank 1 BUT I AM NOT POSITIVE which one was longer. I mention this because when I went to the Toyota parts department, they list the Bank 1 and Bank 2 AF heated sensor as two different part numbers.

I hope that some can benefit from my suffering.

Just some basic facts:
Sensor failed (confirmed by heater circuit reading OPEN) at around 94K miles; Sienna 2002 XLE

[deanus]

Finally got it together. Bank 1 was indeed a try of any former 68 Cadillac owners patience. A lot of fingertip work and painful forearm damage. Fortunately I had a "nurse" handing me whatever tools I thought I needed to throw into the mix. Anyway, someone on here somewhere mentioned https://www.1sttoyotaparts.com/partscat.html
where you can find the sensors for $148. A bargain.
The engine lights went off by unhooking the battery after changing the sensors. My mileage doesn't seem to be a whole lot better than 22mpg but at least the lights are off. Most thanks to Qslim for helping me figure out that autozones code description was wrong.

[Qslim]

Glad you got it hooked up.