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- Plano, Texas, USA
Thanks for the update. Yes you definitely had the same problem as the OP on coolant control valve.
2019 CX-5 Coolant problem (CEL = P0126)
- Thread starter kolz2788
- Start date
Here is an updated TSB from Mazda on this coolant control valve issue. They have provided some new information which is helpful, however there is still at least one unresolved major issue still remaining IMO.
They're saying that the low temp issue is caused by a production defect with the internal mechanical thermostat, which ironically is described as the 'failsafe' thermostat in the TSB. They also provided a cutoff manufacturing date of 11/16/2020, which they say is the point in time where the manufacturing defect was corrected. So it's definitely helpful to finally know what the root cause of this problem is, and how to identify the corrected part. Now if they had identified and corrected the issue at that point, one obvious question would be why it took another 5 months to get this information released. I'm not going to hold my breath waiting for an answer to that one.
But a far more important question related to this issue is why Mazda has not (so far anyway) turned this into an SSP. It's all well and good if one of the affected vehicles has a severe case, where either a P0126 code is set, the blue light stays on, or the vehicle heat is very poor in Winter time. I suspect that most of those situations have already been identified and corrected. However, what about the less severe cases, where the coolant temps are low, but not so much so that most owners would be aware of the problem?
Running engine consistently and significantly below design temp (i.e. 170F or lower), is likely to result in sludge, and it's all downhill from there. Now I have no idea how many defective thermostats were installed into vehicles over the years, but I can't understand Mazda rolling the dice by hoping that number is low enough to not impact them long-term. In their TSB, Mazda's only reference to the frequency of the defect is: 'due to production variety of the failsafe thermostat'. So 'variety' must be some number greater than 1, but (probably) less than 1 million.
Personally, I know that our two CX-5 are ok, simply via the OBD ECT temp readings. However, that type of monitoring is something that very few owners are doing. But I know that these auto forums attract a number of individuals who do that stuff. So this is a heads-up to everyone who owns an affected vehicle on the list from the TSB, to check the coolant temps (or have them checked by a shop). The fully warmed-up ECT temp from OBD should remain somewhere around an average of 195F. Temps will of course vary a bit, especially idling in stop-and-go, where it will head up toward 210F and then back down again when the fan comes on.
Perhaps Mazda will rethink the possible long-term impact of a bunch of defective thermostats in their vehicles, and do the right thing by taking proactive action to find and replace them. All they would need to do is confirm that the OBD temps are indeed getting to, and maintaining the target design running temp. Not a big deal at all for them IMO. One can hope I guess.
They're saying that the low temp issue is caused by a production defect with the internal mechanical thermostat, which ironically is described as the 'failsafe' thermostat in the TSB. They also provided a cutoff manufacturing date of 11/16/2020, which they say is the point in time where the manufacturing defect was corrected. So it's definitely helpful to finally know what the root cause of this problem is, and how to identify the corrected part. Now if they had identified and corrected the issue at that point, one obvious question would be why it took another 5 months to get this information released. I'm not going to hold my breath waiting for an answer to that one.
But a far more important question related to this issue is why Mazda has not (so far anyway) turned this into an SSP. It's all well and good if one of the affected vehicles has a severe case, where either a P0126 code is set, the blue light stays on, or the vehicle heat is very poor in Winter time. I suspect that most of those situations have already been identified and corrected. However, what about the less severe cases, where the coolant temps are low, but not so much so that most owners would be aware of the problem?
Running engine consistently and significantly below design temp (i.e. 170F or lower), is likely to result in sludge, and it's all downhill from there. Now I have no idea how many defective thermostats were installed into vehicles over the years, but I can't understand Mazda rolling the dice by hoping that number is low enough to not impact them long-term. In their TSB, Mazda's only reference to the frequency of the defect is: 'due to production variety of the failsafe thermostat'. So 'variety' must be some number greater than 1, but (probably) less than 1 million.
Personally, I know that our two CX-5 are ok, simply via the OBD ECT temp readings. However, that type of monitoring is something that very few owners are doing. But I know that these auto forums attract a number of individuals who do that stuff. So this is a heads-up to everyone who owns an affected vehicle on the list from the TSB, to check the coolant temps (or have them checked by a shop). The fully warmed-up ECT temp from OBD should remain somewhere around an average of 195F. Temps will of course vary a bit, especially idling in stop-and-go, where it will head up toward 210F and then back down again when the fan comes on.
Perhaps Mazda will rethink the possible long-term impact of a bunch of defective thermostats in their vehicles, and do the right thing by taking proactive action to find and replace them. All they would need to do is confirm that the OBD temps are indeed getting to, and maintaining the target design running temp. Not a big deal at all for them IMO. One can hope I guess.
Agreed about the basis for the name - I was just poking a bit of fun at them for using that word to describe the part that's turned out to be the cause of this problem. IMO it might have been better to call it something like 'internal mechanical' instead of 'failsafe' for this particular document.
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- Plano, Texas, USA
Thanks for the update.
If Mazda was not willing to cover “coolant control valve” replacement under powertrain warranty which in fact includes defective mechanical thermostat and the thermostat is indeed on the parts list covered under powertrain warranty, what do you expect Mazda will do for this issue?
Just look at the cylinder deactivation issue on fallen rocker arms, which is more serious as the problem could cause person’s life, the recall Mazda issued doesn’t even include a simple check on whether or not if any of the rocker arms has fallen before the PCM update. Cutting corners in such manner for a safety issue is ridiculous to me!
I never expect automakers to do much of anything voluntarily and proactively - just hoping they might.
Just a revival of an issue that has obviously been around for a while.
My wife has a 2020 CX-5 with 12,800 miles throwing the PO126 code and the dealer is quoting July before the parts are available. I even tried to trade it in, and they said due to the problem they'd offer me 19K. Couple other dealers the same. Carvana doesn't even want it. I've tried their FB page, Mazda USA and many other avenues
I have been birddogging this for over a week and have gotten nowhere YET. If anyone has any magical tricks, I am all ears. I have been buying new Mazda's for FORTY years and have only had one other problem which again they ran and hid on (clutch disc falling apart on a mazda 6.
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- Plano, Texas, USA
Your 2020 CX-5 with 12,800 miles still has new vehicle warranty. And you’ve contacted Customer Experience Center, Mazda North American Operations about the issue and they didn’t offer anything to help you? I’ve seen people are getting the free loaner car from Mazda dealer for months while waiting for the engine to get replaced. MNAO has obligation to fix your CX-5 within reasonable amount of time, and should provide something for you to drive if your CX-5 isn’t drivable waiting for warranty repair. And MNAO should be able to source a coolant control valve from somewhere, even can pull one out from a brand new CX-5. What you’ve experienced is unbelievable to me and shouldn’t be happening.
If you read the TSB, there’re 2 parts which are needed to fix the problem:
PYFD-15-16Z Valve, Water Control (O-ring included)
PYFB-15-169 Gasket, Water Outlet (for Lower radiator hose component)
If you googled them, there’re still available at some Mazda dealers such as:
MNAO should be able to locate these parts from these Mazda dealers and send them to your Mazda dealer. The worst case you can purchase these 2 parts, take (or tow by free Mazda Roadside Assistance) your CX-5 to your Mazda dealer with 2 parts you have let them fix the problem according to the TSB, and get reimbursed from MNAO later.
Your treatment by MNAO is simply unbelievable!
I agree 1000%.
Per the dealer they have the valve on hand. The issue is the latest TSB requires 3 additional parts
PYFB15113 (washer),
PYFB15169 (gasket)
PE1375296 connector
All 3 are unavailable until July. They say the previous TSB's did not require the above parts and they have done MANY without a problem. However Mazda will not authorize or pay for the repair using the previous method. They also said due to the fact Mazda knows the parts aren't available I can pay for the repairs myself (which may affect the warranty) or continue to drive the car until July. neither of the above is going to happen. I have opened a case with the BBB and posted on their FB page. They messaged they would respond promptly. I'm not holding my breath. I do not know what is going on with the US operations but they are about to lose a 40 year repeat customer.
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A couple minutes ago, I selected the 2 original parts and the 3 new ones for purchase from a Mazda online site. Naturally I didn't actually buy anything, but all of those parts appeared to be in stock at that site and ready to ship today. It wasn't the Mazda site that yrwei52 posted, but it wouldn't come as a surprise if that one has all of the parts in stock as well.
Not sure what's going on with your stealership, but perhaps they're simply not putting enough effort into this for you.
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- Plano, Texas, USA
Not sure why these additional washer、gasket、connector are so important to fix the stuck-open thermostat problem within the water control valve as the fix is just to replace the faulty water control valve. I guess your choice is limited as MNAO apparently believe leaving the CEL on with P0126 code is fine to your vehicle. You can keep driving the CX-5 but it’d be tougher during the winter time with the thermostat stuck open.
This’s another problem related to cylinder deactivation as the water control valve is something new to accommodate the CD feature on the 2.5L NA and looks like it’s been causing problems since then.
If you look at the last page of the TSB it shows this applies to 2.0 engines as well as 2.5 with and without CD
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- Plano, Texas, USA
I believe TJP has been dealing with Mazda North American Operations directly right now but he’s getting nowhere. And for some reason the Customer Experience Center, Mazda North American Operations is unresponsive and is really hard to get to a live person right now!
How does one actually get through to Corporate Mazda Customer support?
I did call a few places last week and all said not available. Even a few of the sites that showed the parts as being in stock, when called admitted to not having them. that's not to say one doesn't SOMEWHERE but I've got a ton of hours in this mess with ZERO support so far. I am hoping for a change tomorrow but not counting on it
Do you have a copy of the latest TSB or know where to view one ? Thanks
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- Plano, Texas, USA
Yes, that table is a general operation number / labor hours on warranty for ALL models.
And these are applicable models to the problem from the TSB:
APPLICABLE MODEL(S)/VINS
2019-2021 Mazda3
2018-2021 (US spec) / 2019-2021 (Mexico spec) Mazda6 2019-2021 CX-3
2018-2021 CX-5
2020-2021 CX-30
NOTE: Vehicles with SKYACTIV-G 2.5T (turbo) are not applicable.
Of course the water control valve is something new on the 2.5L since Mazda introduced the cylinder deactivation to it.
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Ok, again I didn't actually put the order in, so what you've (sadly) discovered could also be true for the site I was using as well. If you haven't already tried them, it's https://www.jimellismazdaparts.com/I did call a few places last week and all said not available. Even a few of the sites that showed the parts as being in stock, when called admitted to not having them. that's not to say one doesn't SOMEWHERE but I've got a ton of hours in this mess with ZERO support so far. I am hoping for a change tomorrow but not counting on it
So they added a water control valve to the 2.0 and non-CD 2.5L engines as well?
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- Plano, Texas, USA
The water control valve was added at the time Mazda modified the 2.5L NA for cylinder deactivation for 2018 CX-5. They didn’t use this valve on the 2.5T when Mazda added the turbo to the 2.5L NA for 2016 CX-9. From part description the water control valve PYFD-15-16ZA isn’t for the 2.5T、the 2.0L、and the 2.5L not from Japan.
DETAILS
- Genuine:
- SKU: PYFD-15-16ZA
- Description:
2019-21. CX-5. Without turbo. CX-3. Mazda3. Japan built, auto trans. CX-30. 2.5L non turbo. auto trans. 2.5L 2018-20. - Applications: 2.5L. 2019-20.
- Replaces: PYFB-15-16ZA, PYFD-15-16Z
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