Dangerous cylinder deactivation trouble on 2018 CX-5 and Mazda6 models

Hey guys!
I had my CX-5 taken to the service shop this morning. They took about an hour to work on the PCM update. They told me that the reprogram is complete and firmware has been updated. I do not see my trips reset or favorites lost on the infotainment, like most of them reported here of disconnecting battery before the update. Anybody else who had the same experience?
Did they actually do it? Any way to confirm this?
I don't see the firmware version on the invoice either... dang!

Thanks in advance.
2018 CX-5 Touring
Mazda really should list the version on the invoice. Otherwise, people will be wondering forever if anything was actually done.

They've got to step up and do everything in their power to give people confidence in the fix.
Yes Mazda dealer should provide PCM version number on the invoice like jjm86m's Mazda dealer did after the dealer fixed his rocker arm fallen problem. I was given PCM version on the invoice when I got PCM update for Flexible oil life monitor problem.

If a Mazda dealer can't provide PCM version number, that does make people wonder if they know which version of PCM software they need to use for this cylinder deactivation recall.

My original PCM software was F0008XDX. It was reflashed F0010XDX
BTW, how did you get the firmware version out of your PCM?
It was on my service report for the work completed on my CX5. I didn't go in and check it myself.
 
I wonder if you can see any change after connecting to Forscan after the firmaware action at Mazda dealer.

I seeing PCM Power Train Control Module strategy code, is not like F0010XDX but PYL3-188K2-E, maybe
this may change after the upgrade and it will be a way to confirm the service action carried out.
 
I wonder if you can see any change after connecting to Forscan after the firmaware action at Mazda dealer.

I seeing PCM Power Train Control Module strategy code, is not like F0010XDX but PYL3-188K2-E, maybe
this may change after the upgrade and it will be a way to confirm the service action carried out.
Yeah the PCM version "F0010XDX" printed on jjm86m's invoice does sound strange. By reading my original TSB 01-019/15 dated on 8/6/2015, and the latest TSB 01-008/19 dated on 2/08/2019 for "Engine Oil Flexible Maintenance Notification Does Not Work", there're PCM calibration part number and file name for PCM firmware update. My updated PCM calibration p/n is "PYAV-188K2-C" on Denso for 2016 CX-5 4WD at the time. Now there's a newer version, "PYAV-188K2-E", for the same problem. I believe "F0010XDX" could be just the "file name".
 
It looks like you are very close to the truth. I just found this: https://static.nhtsa.gov/odi/rcl/2019/RCRIT-19V497-3997.pdf

...and I think that F0010XDX is the manufacturer's internal operation number, while PYAV-188K2-C is an example PCM file name. Interestingly, this file name can be read using Forscan, no need to connect the original Mazda MDS diagnoscope.

Here You can find more pdf documents about that recall:

https://www.nhtsa.gov/vehicle/2018/MAZDA/MAZDA6/4%2520DR/FWD#recalls

Some interesting words:

"The rocker arm comes out of position only when a switch between cylinder deactivation/activation
occurs, and the software program to increase oil pressure to hydraulic valve adjusters is incorrect.
If the rocker arm starts to come out of position during this switch, there is a threshold for full separation
and partial separation.
* In partial separation condition, the rocker arm maintains close alignment to intended operating
position, and will return to normal position quickly with no effect on engine performance.
* In full separation condition, the rocker arm alignment passes the partial separation threshold
and will move fully out of position, causing damage to the engine.

Since the remedy software corrects the oil pressure control program of the hydraulic valve clearance
adjuster, if a customer did not already experience engine damage or engine failure due to the defect,
they will not have related issues after they have the remedy completed."
 
It looks like you are very close to the truth. I just found this: https://static.nhtsa.gov/odi/rcl/2019/RCRIT-19V497-3997.pdf

...and I think that F0010XDX is the manufacturer's internal operation number, while PYAV-188K2-C is an example PCM file name. Interestingly, this file name can be read using Forscan, no need to connect the original Mazda MDS diagnoscope.

Here You can find more pdf documents about that recall:

https://www.nhtsa.gov/vehicle/2018/MAZDA/MAZDA6/4%2520DR/FWD#recalls

Some interesting words:

"The rocker arm comes out of position only when a switch between cylinder deactivation/activation
occurs, and the software program to increase oil pressure to hydraulic valve adjusters is incorrect.
If the rocker arm starts to come out of position during this switch, there is a threshold for full separation
and partial separation.
* In partial separation condition, the rocker arm maintains close alignment to intended operating
position, and will return to normal position quickly with no effect on engine performance.
* In full separation condition, the rocker arm alignment passes the partial separation threshold
and will move fully out of position, causing damage to the engine.

Since the remedy software corrects the oil pressure control program of the hydraulic valve clearance
adjuster, if a customer did not already experience engine damage or engine failure due to the defect,
they will not have related issues after they have the remedy completed."

Yeah the PCM version "F0010XDX" printed on jjm86m's invoice does sound strange. By reading my original TSB 01-019/15 dated on 8/6/2015, and the latest TSB 01-008/19 dated on 2/08/2019 for "Engine Oil Flexible Maintenance Notification Does Not Work", there're PCM calibration part number and file name for PCM firmware update. My updated PCM calibration p/n is "PYAV-188K2-C" on Denso for 2016 CX-5 4WD at the time. Now there's a newer version, "PYAV-188K2-E", for the same problem. I believe "F0010XDX" could be just the "file name".

I wonder if you can see any change after connecting to Forscan after the firmaware action at Mazda dealer.

I seeing PCM Power Train Control Module strategy code, is not like F0010XDX but PYL3-188K2-E, maybe
this may change after the upgrade and it will be a way to confirm the service action carried out.

Yes Mazda dealer should provide PCM version number on the invoice like jjm86m's Mazda dealer did after the dealer fixed his rocker arm fallen problem. I was given PCM version on the invoice when I got PCM update for Flexible oil life monitor problem.

If a Mazda dealer can't provide PCM version number, that does make people wonder if they know which version of PCM software they need to use for this cylinder deactivation recall.

Appreciate all your inputs, thanks guys.
I'm gonna try connecting to a Forscan (gotta buy one from amazon, if you have any suggestions, please chip in) this weekend and get back on this.

Is it even possible to update/reprogram the PCM without disconnecting the battery? A lil bit of Google suggests removing the negative battery cable as step 1.
 
Appreciate all your inputs, thanks guys.
I'm gonna try connecting to a Forscan (gotta buy one from amazon, if you have any suggestions, please chip in) this weekend and get back on this.

Is it even possible to update/reprogram the PCM without disconnecting the battery? A lil bit of Google suggests removing the negative battery cable as step 1.

Check out this post in another thread on this topic regarding disconnecting the battery/pulling fuses.
 
I tortured the Polish Mazda branch and finally received an email that I could arrange to upload new software.
I wonder if they are going to announce a service action or if they want to upload the update quietly during warranty inspections. (uhm)
 
I found Mazda's patent (US20150377151A1) that describes the cylinder deactivation mechanism. Like any patent, it's not light reading, and there's an extra layer of difficulty because it's been translated from the original Japanese. However, if you're willing to slog through it, you'll get a very good understanding of how CD is implemented. Interestingly, the patent isn't limited to cylinder deactivation. Discussion of the variable valve timing system is interwoven through the document. The unifying theme is that both systems are controlled by a variable capacity oil pump.

I won't try to summarize it beyond noting that it confirms the default condition is for all four cylinders to be operative. The pin that locks the HLA in its extended position is engaged by a spring. To deactivate the cylinder, the pin is driven inward (disengaged) with oil pressure, allowing the HLA to be compressed (shortened) by the cam, thereby stopping the open/shut movement of the intake and exhaust valves.

After studying the patent's drawings and descriptions, I'm more convinced than ever that the reason the rocker falls off is that the HLA is somehow inhibited from springing back to its extended length, which creates a gap between the top of the HLA and the rocker. Unfortunately, there isn't enough detail in the patent to figure out what is responsible for inhibiting the HLA from extending. I hope the cause is entirely a function of the oil pressures that are being tweaked by Mazda's reprogramming of the PCM in the recall.
 
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Lets hope! It is still amazing to me (a car novice) that changes in oil pressure is what moves that pin. I always thought oil in the engine was just for lubrication and nothing else!
 
I looked through this document and the cd system looks damn complicated.
In my opinion the game is not worth the candle. I am rather pessimistic about the durability of such solutions.
I would prefer a classic engine without such inventions.
 
I found Mazda*s patent (US20150377151A1) that describes the cylinder deactivation mechanism. Like any patent, it*s not light reading, and there*s an extra layer of difficulty because it*s been translated from the original Japanese. However, if you*re willing to slog through it, you*ll get a very good understanding of how CD is implemented. Interestingly, the patent isn*t limited to cylinder deactivation. Discussion of the variable valve timing system is interwoven through the document. The unifying theme is that both systems are controlled by a variable capacity oil pump.

I won*t try to summarize it beyond noting that it confirms the default condition is for all four cylinders to be operative. The pin that locks the HLA in its extended position is engaged by a spring. To deactivate the cylinder, the pin is driven inward (disengaged) with oil pressure, allowing the HLA to be compressed (shortened) by the cam, thereby stopping the open/shut movement of the intake and exhaust valves.

After studying the patent*s drawings and descriptions, I*m more convinced than ever that the reason the rocker falls off is that the HLA is somehow inhibited from springing back to its extended length, which creates a gap between the top of the HLA and the rocker. Unfortunately, there isn*t enough detail in the patent to figure out what is responsible for inhibiting the HLA from extending. I hope the cause is entirely a function of the oil pressures that are being tweaked by Mazda*s reprogramming of the PCM in the recall.

Interesting that the car has a variable capacity oil pump. Is that a common thing in cars? I had assumed that the pressure managing the HLA on #1 and #4 would have been a mechanism located specifically at those two points (directed nozzles), and not management of the engine-wide pressure.

I wonder what the range of the operating pressure is (are we talking a swing in a few psi, or is it a 10+ psi variation), and how the changes in pressure during engine operation might affect global lubricating performance. Any car I have ever had with an oil pressure gauge has always operated at a steady pressure, other issues (like being down a quart) notwithstanding. This also raises other weak points in the system, like having one's oil always topped off so as to maintain peak pressure in the system rather than introducing risk of low-pressure failure.

Or do I misunderstand, and that variable capacity pump is dedicated to this function, and there is a separate pump for the engine in general?
 
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... I had assumed that the pressure managing the HLA on #1 and #4 would have been a mechanism located specifically at those two points (directed nozzles), and not management of the engine-wide pressure...

Although the engine-wide oil pressure is regulated in response to a lot of engine parameters, the oil pressure change seen by the HLAs that turns CD on/off is controlled by a couple direction switching valves (number 46 and 47 in the schematic at figure 4).

k0bDaYI.jpg


Here's a picture of those valves. I assume the holes of different sizes at the two locations control both the direction of oil flow and the oil volume/pressure.

oYBi9w0.jpg
 
Although the engine-wide oil pressure is regulated in response to a lot of engine parameters, the oil pressure change seen by the HLAs that turns CD on/off is controlled by a couple direction switching valves (number 46 and 47 in the schematic at figure 4).

k0bDaYI.jpg


Here's a picture of those valves. I assume the holes of different sizes at the two locations control both the direction of oil flow and the oil volume/pressure.

oYBi9w0.jpg

Thanks for that.

That's a lot of precision in an environment where so many violent actions occur.

Fascinating stuff. (Interesting that those valves are made in Germany).
 
CD can be monitored on a 2019 Mazda 3

https://youtu.be/E93HOqEMteo

Looks like you can monitor CD activities on a 19 3 according to this review(See 10:23). Perhaps it works the same for CX-5 that has CD feature. It appears that it can be deactivate/activate way too often. Therefore, more chance something will go wrong. I don't feel good about this at all. Wish I can permanently turn the CD feature off.
 
CD can be monitored on a 2019 Mazda 3

https://youtu.be/E93HOqEMteo

Looks like you can monitor CD activities on a 19 3 according to this review(See 10:23). Perhaps it works the same for CX-5 that has CD feature. It appears that it can be deactivate/activate way too often. Therefore, more chance something will go wrong. I don't feel good about this at all. Wish I can permanently turn the CD feature off.

I doubt it on the CX-5 because it's part of the new infotainment system on the 3.

You're right. It's a mess. I just eliminated a new 3 for my wife solely on the basis of CD. Good luck to all who have it.
 
You're right. It's a mess. I just eliminated a new 3 for my wife solely on the basis of CD. Good luck to all who have it.

People like us (that are regulars on car forums), know about this problem. Most car buyers though are not forum members.
Makes me think then that the majority of car shoppers that are looking at Mazda's right now are blissfully unaware of the CD issue, and end up buying the vehicle based on the sales pitch.
I mean, as an example, if every prospective CR-V buyer was aware of the oil dilution issues with Honda, how many would walk away from it?
I'm guessing most, if not all, Honda buyers are also blissfully unaware of the issues, just like most Mazda buyers are unaware of the CD issues.
There are just so many car buyers out there that simply do not do any research or any due diligence when buying a vehicle.
Other than a house, it's the most expensive purchase anyone is likely to make, and yet the majority of buyers do diddly squat to educate themselves before buying.
I just don't get it.
Like you, I will not purchase another Mazda that comes equipped with the CD feature. I'm so glad my 2017 doesn't have it.
I have also stopped recommending Mazda to my friends until they get this mess sorted out.
 
I don't feel good about this at all. Wish I can permanently turn the CD feature off.

I wonder if enough people made a stink about it they would allow new software that simply disables it.... seriously. It should be easy. It could be optional for owners. Installation under control of the dealers. It would cost the company little.

But you'd have to be really loud and persistent about it. And there'd have to be a good number of you requesting/demanding it.
 
Not as easy as it should be because MAZDA may be forced to resubmit the engine for mileage and smog regulations. Hopefully someone with really good engineering skills will figure out how to disable it without causing other issues. Maybe MAZDA engineers will do it without forcing a resubmission's. Glad I have my 2014 with 52,000 miles that runs and looks like new. Ed
 
Not as easy as it should be because MAZDA may be forced to resubmit the engine for mileage and smog regulations. Hopefully someone with really good engineering skills will figure out how to disable it without causing other issues.

That's an even better idea.

Chris, do you think Orange Virus or VersaTuner could do it? Or anyone?
 
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