Sensor catalytic converter, cylinder deactivation - Solved

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CX-5 GT 2018
Dear All,

I'm the owner of a CX-5 2018 GT AWD 2.5L NA with cylinder deactivation. I unfortunately managed to damage a sensor (the wire has ripped off the connector, unrecoverable) found under the car on the catalytic converter pipe. I blame a block of hard snow/ice.

The error code reads P2BF6, vehicle system malfunction. Went to dealership, of course one cannot replace only the sensor (part number for the sensor itself seems to be PYH5-13J40) but the whole pipe + converter (PYH6-20-55XA) which is quite costly...

The mechanics was a bit vague has to what the purpose of this sensor was. It was mentioned it had to do with the cylinder deactivation feature. Mazda itself, when contacted, was also a bit clueless and kept referring me back to my dealership.

I couldn't find much info on the web/forums, there's a TSB for mazda3 about same error code but my case is a bit different and it didn't really say what this sensor was actually doing.

My question to you, fellow owners, would be if anyone knows what would be the consequences of driving without that obscure sensor functioning? If it just prevents the car from deactivating cylinders, I wouldn't care, even better I want to say! But maybe that's just wishful thinking..

Thanks in advance!

Stay safe.
 
Did it throw a CEL? If so was it solid or flashing.
Maybe you found a way to disable Cylinder Deactivation. Can you drive and verify that CD is still functioning? Is there a display that shows it in operation (think the European variant has a screen showing the cylinders)?
 
No Check Engine Light. All I have is this generic warning icon in info (triangle with exclamation point).
I drove the car a few times, couldn't notice anything unusual. I can't tell in my case if CD is on/off, I don't have the infotainment version that allows you to see if running on 4 or 2 cylinders unfortunately.
Here's a picture of the sensor in question I managed to take, you can see the connector being scraped (it's actually worse, the pins come off so really can't repair it am afraid)..
Img_2021_03_20_16_18_49.jpeg
 
...
Here's a picture of the sensor in question I managed to take, you can see the connector being scraped ....

It appears that the attachment of that sensor on my 2020 is not exactly the same as on your vehicle, where mine is attached with 3 torx bolts. However, although I can't tell for certain from your pics, it appears to me that yours is also attached with bolts, which of course can be undone. So I can't understand why any removable sensor with a separate part number stamped on it would not be able to be replaced.

I suggest pushing Mazda on this, and see if you can get them to put more effort into finding this sensor as a separate, replaceable part.
 
Dear All,

I'm the owner of a CX-5 2018 GT AWD 2.5L NA with cylinder deactivation. I unfortunately managed to damage a sensor (the wire has ripped off the connector, unrecoverable) found under the car on the catalytic converter pipe. I blame a block of hard snow/ice.

The error code reads P2BF6, vehicle system malfunction. Went to dealership, of course one cannot replace only the sensor (part number for the sensor itself seems to be PYH5-13J40) but the whole pipe + converter (PYH6-20-55XA) which is quite costly...

The mechanics was a bit vague has to what the purpose of this sensor was. It was mentioned it had to do with the cylinder deactivation feature. Mazda itself, when contacted, was also a bit clueless and kept referring me back to my dealership.

I couldn't find much info on the web/forums, there's a TSB for mazda3 about same error code but my case is a bit different and it didn't really say what this sensor was actually doing.

My question to you, fellow owners, would be if anyone knows what would be the consequences of driving without that obscure sensor functioning? If it just prevents the car from deactivating cylinders, I wouldn't care, even better I want to say! But maybe that's just wishful thinking..

Thanks in advance!

Stay safe.
Here’s my research:

9580C811-E6EF-4ED2-8BA4-8C8D80830243.jpeg

4F59BE2A-8C6D-4B07-AED9-BEEF2AE92F28.jpeg

A21A697F-DF5A-427A-BF12-CB9A93853988.jpeg

39C55255-EE58-4934-BF8C-A8CA2CEE73A2.jpeg


The exhaust components’ schematic shows there’re 2 types of catalytic converters, PYE9-20-55X (Type A) and PYH6-20-55XA, for 2018 CX-5 GT AWD which has 2.5L. But the description says the formal (Type A) is not for cylinder deactivation. This means your catalytic converter has additional components for CD, hence it’s more expensive. Unfortunately your broken sensor could be one of the additional components on catalytic converter for CD, and Mazda believes they don’t want to sell those additional components separately even if the components or sensors can be removed from the catalytic converter.

If I were you, I’d get this “damage” covered by insurance. If you don’t want to go through the insurance thinking the rate hike may not be worth it, you can try salvage yard finding one and either replace the sensor part only if it’s really removable, or just replace the whole catalytic converter and pipe.
 
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It appears that the attachment of that sensor on my 2020 is not exactly the same as on your vehicle, where mine is attached with 3 torx bolts. However, although I can't tell for certain from your pics, it appears to me that yours is also attached with bolts, which of course can be undone. So I can't understand why any removable sensor with a separate part number stamped on it would not be able to be replaced.

I suggest pushing Mazda on this, and see if you can get them to put more effort into finding this sensor as a separate, replaceable part.
Thanks for your answer. Yeah I tried convincing Mazda (Canada) twice but alas they said sensor comes with the whole thing only..
 
Here’s my research:

View attachment 296672
View attachment 296673
View attachment 296674
View attachment 296675

The exhaust components’ schematic shows there’re 2 types of catalytic converters, PYE9-20-55X (Type A) and PYH6-20-55XA, for 2018 CX-5 GT AWD which has 2.5L. But the description says the formal (Type A) is not for cylinder deactivation. This means your catalytic converter has additional components for CD, hence it’s more expensive. Unfortunately your broken sensor could be one of the additional components on catalytic converter for CD, and Mazda believes they don’t want to sell those additional components separately even if the components or sensors can be removed from the catalytic converter.

If I were you, I’d get this “damage” covered by insurance. If you don’t want to go through the insurance thinking the rate hike may not be worth it, you can try salvage yard finding one and either replace the sensor part only if it’s really removable, or just replace the whole catalytic converter and pipe.
Thanks for your answer. Yes there's something about it being used for CD but I still don't know if I could simply live with it without fixing it. No one at Mazda seem to know the answer, or perhaps they don't want to say..
I found those pictures online that shows the sensor on top of what looks like a valve. So for some reason this wouldn't exists for non-CD models? Am not sure if it is part of exhaust pie or perpendicular to it..
image_2.jpeg
image.jpeg
 
Thanks for your answer. Yes there's something about it being used for CD but I still don't know if I could simply live with it without fixing it. No one at Mazda seem to know the answer, or perhaps they don't want to say..
I found those pictures online that shows the sensor on top of what looks like a valve. So for some reason this wouldn't exists for non-CD models? Am not sure if it is part of exhaust pie or perpendicular to it..View attachment 296680View attachment 296681
You have an error code P2BF6 and a warning message for vehicle system malfunction. If you’re going to live with it without trying to fix it, you won’t be able to get by with this for annual vehicle inspection if there’s one. Or when you sell the car you may have issues from it. In any event I’d try to fix the problem if I were you, especially it’s a fairly new 2018 CX-5.

Other than going through the insurance、or getting a used catalytic converter, you may try to take the damaged sensor out、find all information on it possibly the part number, then go through Mazda OEM parts sellers overseas (japanparts.com、www.parts-sale.jp、partsouq.com, etc.) to get the sensor if possible.
 
I know I'm not being helpful here, but I gotta say, the more I read about CD (in any vehicle), plus any type of start stop technology, just to get an extra 1 or 2 miles/gal, is just not worth it.
Whatever my next vehicle will be, it will not have these features: CD, start/stop, or a CVT.
Car manufacturers have had over a hundred years to develop and refine internal combustion engines, and the gas mileage today is not much better than it was when the Ford model T ruled the roads.
 
The complexity and the high costs of fixing them when they break in modern cars is astounding. The government forced this on us. Mazda didn't add CD to make the cars more attractive to buyers. Mazda should have protected that part better. When it is warmer I will crawl under mine and take a look at it to see how vulnerable it is.
 
Thanks for your answer. Yes there's something about it being used for CD but I still don't know if I could simply live with it without fixing it. No one at Mazda seem to know the answer, or perhaps they don't want to say..
I found those pictures online that shows the sensor on top of what looks like a valve. So for some reason this wouldn't exists for non-CD models? Am not sure if it is part of exhaust pie or perpendicular to it..View attachment 296680View attachment 296681
There must be an electric motor in it to turn the butterfly.
 
There must be an electric motor in it to turn the butterfly.
Yes, it's a 5 wire connector - 2 for the shutter valve motor, and the other 3 wires are reference, ground, and signal for the shutter valve sensor.

Seems that there's no end to all of the wonderful new gifts that CD has brought to us :rolleyes:
 
... I unfortunately managed to damage a sensor (the wire has ripped off the connector, unrecoverable) ...
Putting aside the subject of finding a replacement sensor/connector for a moment, I have a question about your statement above. By 'unrecoverable', I think this means 'unrepairable'. Is that correct? If so, can you post how and by whom this damaged part was determined to be unrepairable?

In my experience, what one person considers to be unrepairable is very often easily fixed by someone else who has more knowledge and skill. And when the repair bill is going to be $1K or more, I'd want to be 100% certain that the damage is truly unrepairable. At the very least, I'd unbolt and remove the sensor from the mount point on the cat assembly and do a bit of testing with a meter, in order to try to determine the full extent of the electrical damage.

I'm not saying that I could fix this damaged part, only that I would always give it my best attempt. However, just based on the picture that you posted, I would also be willing to lay a fairly sizeable wager that any competent auto electric shop could fix it.
 
Putting aside the subject of finding a replacement sensor/connector for a moment, I have a question about your statement above. By 'unrecoverable', I think this means 'unrepairable'. Is that correct? If so, can you post how and by whom this damaged part was determined to be unrepairable?

In my experience, what one person considers to be unrepairable is very often easily fixed by someone else who has more knowledge and skill. And when the repair bill is going to be $1K or more, I'd want to be 100% certain that the damage is truly unrepairable. At the very least, I'd unbolt and remove the sensor from the mount point on the cat assembly and do a bit of testing with a meter, in order to try to determine the full extent of the electrical damage.

I'm not saying that I could fix this damaged part, only that I would always give it my best attempt. However, just based on the picture that you posted, I would also be willing to lay a fairly sizeable wager that any competent auto electric shop could fix it.
You're right, someone that knows a bit of electronic could have perhaps find a way to repair it. The dealership told me it was not repairable but I guess dealerships don't repair, they replace.. I then went on having a long email thread with Mazda Canada providing pictures and all but alas they also said that unfortunately the whole cat converter assembly had to be replaced. It's just a bit frustrating that they don't sell only that part... In all cases, I think I'll go ahead with replacement and maybe try to fix the old one and sell it somewhere or maybe sell it as is, not sure if there's a market for that.
Thanks all for your comments and help. I was getting a bit disappointed by Mazda (well, I am still a bit 😉) but the sense of community on this forum cheered me up!
 
Sorry to hear about this Lenny.

Someone at Mazda knows what this part does or it wouldn’t be on the car. It shouldn’t be so hard to get and answer and find a more reasonable solution instead of charging 1k by replacing the cat. Seeing things like this make me question if I’m willing to keep my Cx-5s after warranty.

I know a GM mechanic and he sees really weird things all the time but always seems to get help and reasonable explanations from the GM tech line when needed.

There could be some good from this story for people like me and
maybe there is an easy way to deactivate CD.
 
... The dealership told me it was not repairable but I guess dealerships don't repair, they replace.. ....
Yes, the stealerships are terrific at replacing parts, and the more they can replace the better.

I still haven't been able to locate the source supplier of the broken part on your vehicle, but did come up with an alternative that could very well be an inexpensive solution for you. If you do an Ebay search on the secondary part number 706366070, you will come up with 3 results (today anyway) for this part - used, from other vehicles.

One of them has a damaged connector, perhaps caused by something similar to what happened with your vehicle. The part from the other US seller appears to be in good shape, and is described as working.

So, as totally expected, this part can be detached from the portion of the exhaust system that it's connected to, and will take probably all of 5 minutes to replace. It's interesting that all three of these sellers describe the part as an 'actuator', even though it also has a sensor inside of the case as well. Mazda refers to this entire assembly as the 'exhaust shutter valve', so I'm wondering if these Ebay sellers found the word actuator in a description written by the OEM.
 
Yes, the stealerships are terrific at replacing parts, and the more they can replace the better.

I still haven't been able to locate the source supplier of the broken part on your vehicle, but did come up with an alternative that could very well be an inexpensive solution for you. If you do an Ebay search on the secondary part number 706366070, you will come up with 3 results (today anyway) for this part - used, from other vehicles.

One of them has a damaged connector, perhaps caused by something similar to what happened with your vehicle. The part from the other US seller appears to be in good shape, and is described as working.

So, as totally expected, this part can be detached from the portion of the exhaust system that it's connected to, and will take probably all of 5 minutes to replace. It's interesting that all three of these sellers describe the part as an 'actuator', even though it also has a sensor inside of the case as well. Mazda refers to this entire assembly as the 'exhaust shutter valve', so I'm wondering if these Ebay sellers found the word actuator in a description written by the OEM.
Crap, nice find! There's another number below that is different (pct a or b then some numbers) not sure if matters or refers to some kind of date when part was manufactured. I'll try to contact sellers to see if they'd ship my way (am not in US). Thanks!
 
Crap, nice find! There's another number below that is different (pct a or b then some numbers) not sure if matters or refers to some kind of date when part was manufactured. I'll try to contact sellers to see if they'd ship my way (am not in US). Thanks!
I was thinking again about this, maybe the swap is not straightforward because it'd need some calibration... perhaps that's one of the reasons why the part isn't sold separately.
 
I was thinking again about this, maybe the swap is not straightforward because it'd need some calibration... perhaps that's one of the reasons why the part isn't sold separately.
This exhaust shutter appears to be a simple and standard setup, consisting of an actuator to control the shutter flap, and a sensor to monitor the actual flap position. So IMO the ECM would adjust the actuator voltage on-the-fly, in order to get the results it needs to have. I really don't think it's likely that an ECM relearning of the new part would need to be done by Mazda, in order for it to work correctly.

Now all of the above is strictly my opinion, and I certainly could be wrong about that. However, for the amount of money involved to try this out, versus what the stealership is quoting, for me it would be an automatic thing to try. And there's also no risk trying out a used replacement part in this case, simply because what's in there now is dead in the water anyway. So if the used part doesn't work for whatever reason, the ECM is just going to set a code and stop using it, the same as what's happening now.

All of this is JMO, and as always it's your vehicle and your choice.
 
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