2019 CX-5, Coolant problem (CEL = P0126 )

well, it's odd, the VP of the dealership basically told me that Mazda will usually wash their hands with cases like mine because I didn't have it serviced at the dealership. He was an older gentlemen, probably in his 60s.
The President is his nephew and he is likely in his late 30s. Not sure why I mentioned age, but it may be a factor
 
I guess I'm getting confused again. Rockauto and amazon both show
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as the "thermostat" when looking at their site for the 2019 cx-5 2.5 L4....
 
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This Photo seems to show the actual "thermostat portion", wouldn't ya say? definitely seems different than the photo in my previous post...
 
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Southeast MA
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2019 CX-5 GT W/PP
I would go back to the auto body shop that did the repairs and explain all this happening after the repairs. It could all be part of the accident!!
 
I would go back to the auto body shop that did the repairs and explain all this happening after the repairs. It could all be part of the accident!!
It's just very hard to connect those dots. My car was hit in the rear, and the only damage was in the rear. One of the employees @ the mazda dealership said this would be highly unlikely due to the way in which the electricity system is wired.
 
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2020 CX-5 AWD
Since it appears that the OP will be getting the part replaced on Kia's dime, I'm not going to continue posting about the valve on this thread. Although I've learned a few minor things, I don't have anything significant to report so far, and will continue to research this valve. And when there's something worthwhile to say about it, I'll start a new thread (or contribute if someone else starts one first).
 

yrwei52

2016 Mazda CX-5 GT AWD w/Tech Pkg
Contributor
:
Plano, Texas, USA
View attachment 234503 This Photo seems to show the actual "thermostat portion", wouldn't ya say? definitely seems different than the photo in my previous post...
This online parts store has a better illustration on thermostat and coolant control valve (or thermostat housing) for your 2018 CX-5 2.5L with CD. #7 is the traditional mechanical thermostat; #8 is either coolant control valve for 2.5L with CD, or purely a thermostat housing for the rest of 2.5L’s. #9 is the gasket for #8.

Based on the description on coolant control valve, part no. PYFD-15-16Z, it includes thermostat, part no. P502-15-171, and “additional parts” (#9 gasket?). These questions can be easily resolved by visiting the parts department at a Mazda dealer and see the coolant control valve, part no. PYFD-15-16Z, in person to verify.

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Having worked in multiple dealerships, including a Mazda dealership in CT, there seems to be somewhat of an enormous lack of knowledge of how warranty coverage is determined. With Mazda in particular, it is incredibly straightforward. There is a tool called Warranty Wizard on Mazda's internal website. The person at the dealership (service advisor, warranty administrator, whoever) enters the part number that needs replacement- this gives you a labor operation, which is usually something like B1142XRX or something like that. You then put that into Warranty Term Inquiry and that says what the warranty coverage is- basic (3/36) powertrain, emissions, CPO, whatever.

Covering anything beyond what is listed there would be considered goodwill, and would need authorization from Mazda depending on the dollar amount, and Mazda does ask questions about loyalty to dealership, etc. If this part # is listed as covered 3/36, then that's how long Mazda will pay the dealer for replacement of it. Past that, either it has to be processed as a goodwill repair with whatever authorization is needed, or the dealer does not get paid for fixing the car.

There is literally nothing done here that seems like anything out of the norm.
 

yrwei52

2016 Mazda CX-5 GT AWD w/Tech Pkg
Contributor
:
Plano, Texas, USA
Since it appears that the OP will be getting the part replaced on Kia's dime, I'm not going to continue posting about the valve on this thread. Although I've learned a few minor things, I don't have anything significant to report so far, and will continue to research this valve. And when there's something worthwhile to say about it, I'll start a new thread (or contribute if someone else starts one first).
By the illustration found on the Mazda online store you referred, I believe the coolant control valve contains either a mechanical thermostat inside with additional electrical valve assisting the flow control, or a pure motor controlled electrical valve which serves as traditional thermostat functional wise with better flow control by PCM.

Coolant control valve at #8 in above illustration with included invisible thermostat:
6A94528A-99B4-4B7D-B97F-1FD8C44C2978.png




Thermostat housing at the same #8 location with a rounded hole for the thermostat #7:
D92B754A-98A7-42FB-84B0-BE65CFBA871A.png

View attachment 234537
 

yrwei52

2016 Mazda CX-5 GT AWD w/Tech Pkg
Contributor
:
Plano, Texas, USA
Having worked in multiple dealerships, including a Mazda dealership in CT, there seems to be somewhat of an enormous lack of knowledge of how warranty coverage is determined. With Mazda in particular, it is incredibly straightforward. There is a tool called Warranty Wizard on Mazda's internal website. The person at the dealership (service advisor, warranty administrator, whoever) enters the part number that needs replacement- this gives you a labor operation, which is usually something like B1142XRX or something like that. You then put that into Warranty Term Inquiry and that says what the warranty coverage is- basic (3/36) powertrain, emissions, CPO, whatever.

Covering anything beyond what is listed there would be considered goodwill, and would need authorization from Mazda depending on the dollar amount, and Mazda does ask questions about loyalty to dealership, etc. If this part # is listed as covered 3/36, then that's how long Mazda will pay the dealer for replacement of it. Past that, either it has to be processed as a goodwill repair with whatever authorization is needed, or the dealer does not get paid for fixing the car.

There is literally nothing done here that seems like anything out of the norm.
Thanks for the insight. That’s why I believe OP should keep talking to the MNAO, not to his dealership. Unless his Mazda dealer is willing to absorb the possible cost of repair. However, MNAO also relies on dealer’s opinion to make decision on goodwill repair. And the argument here IMO is the definition of “thermostat” described in powertrain warranty. To me, “water control valve” is the “thermostat”, especially the part actually contains the “thermostat”!
 
I'm more so disappointed with how they're just throwing a wide net at the problem and they're not even able to provide me with a differentiation between the coolant control valve and the thermostat.
My car definitely has the following control valve in place..
1610125632636.png


Fingers crossed...

I already had to shell out $109 just to have them look at the car... :[

Edit Just to clarify, I have a 2019 CX5
 
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CX5 2018 GT
I am inclined to think its just a normal thermomechanical thermostat that sits in this so called valve/housing.
I monitor the coolant temp on my screen through OBD and sometimes its behavior is weird i.e opens slowly with small delay of temp variation higher than expected , sometimes quicker. Thats always during the initial opening phase when the car is cold and warms up to operating temp.

Example, sometimes during first fully opening of the thermostat the temp reach 99C then drops sharply to 92-93. Sometimes reach 96 and gradually drop to 92-93 C.
Its like sometimes its just partially stuck and opens abruptly in full open.

Of course the dash doesnt show anything :) the stupid gauge is just fake glued to one position.

If it was purely and only electrically controlled it should be more consistent I think.

Have to go and check on my car and see if any connectors are attached to the valve/housing.
 
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I am inclined to think its just a normal thermomechanical thermostat that sits in this so called valve.
I monitor the coolant temp on my screen and sometimes its lazy i.e open slowly with small delay of temp variation , sometimes quicker.
If it was electrically controlled it would not behave that way.
Havr to go and check on my car and see if any connectors are attached to the valve/housing.
There are electrical connections attached to it.

I'm very inclined to think there is no traditional mechanical thermostat inside the housing based off photos.

My read out of the engine heat is digital.

Maybe your fluctuations are due to differences in air temp/how long the car has been sitting...?
 
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CX5 2018 GT
It usually happens during very hot days. Its just my observation.

Well looking at the real picture of thermostat itself makes me wonder. It just looks mechanical. And it wouldnt usually be separate part if it was all electrically controlled.
The electrical comnection could be a temp sensor.

But again, I am not fully familiar with this and Mazda always surprises me with weird additions like the CD :) so you never know what this is.
Free full tech documentation is limited on gen2 unfortunately.
 
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CX5 2018 GT
Cylinder deactivation

Yes just snapped a pic. You are absolutely correct. There is a large partof the housing with a connector to it. Not temp sensor definetely.
Kind of seems this is new fun stuff for the gen2.

So back to the topic, if that 'valve' element controls thermostat then it should definetely be part of warranty repair (if faulty).

20210108_105857.jpg
 
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yrwei52

2016 Mazda CX-5 GT AWD w/Tech Pkg
Contributor
:
Plano, Texas, USA
Not temp sensor definetely.
Kind of seems this is new fun stuff for the gen2.
Not for all gen-2 CX-5’s. This coolant control valve appears to exist only on 2.5L with CD, cylinder deactivation.
 
:
Pueblo county CO
:
CX-5 Sport 16.5 6M
What would actually 'break' inside something like that in just a few years?

Maybe something inside is just 'crudded' up?
 
What would actually 'break' inside something like that in just a few years?

Maybe something inside is just 'crudded' up?

Not even. 16 Months. The only thing I can think of is that my Coolant was Below L (low) on the reservoir when this problem manifested. I added coolant, and reset the code, hoping that's what it was, but it came back. I guess the remaining coolant could have been concentrated/cruddy, but I don't know..
 
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2018 CX5
If you haven't already call Mazda Customer Service and ask them if they can help out. Even if you don't get service at the dealer, they may split the cost of the repair. Never hurts to ask (they did that for me years ago). Worst they can say is no.
 
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