[ASH8]

This applies to cars with FULL Automatic AC (Air Conditioning) Only.



Mazda in North America has released a bulletin to all Mazda Dealers informing them of an issue with owners complaining of poor AC performance which has actually been around for sometime on multiple models over many years.



The small external Sensor located behind Front Bumper can be out by as much as 50 degrees Fahrenheit or 10 degrees Celsius (under reading) meaning Temperatures outside of car are physically way hotter than what the instrument reading (from Sensor) says it is resulting in the cars AC's not cooling down inside cabin as it should.



Personally I know many owners who have had issues with Mazda's poor AC performance, I trust this finally fixes the problem.



The supplier of the Sensor part to Mazda has rectified the issue with their parts manufacturing process.



See the .Pdf Attached. with more details.
Normal Warranty Period Applies.

 

[Trickster]

Well I am no rocket scientist, but should not that sensor be inside the vehicle? 🤣

 

[RedBaron]

The thing that confuses me is the "50 degrees Fahrenheit or 10 degrees Celsius" statement. 10degC is 18degF, not 50!

@ASH8 is the sensor on the CX50 visible without any (or too much) disassembly, so we can check the lot/date number ourselves?

 

[ASH8]

Well I am no rocket scientist, but should not that sensor be inside the vehicle? 🤣

Clearly you are not, there are Two different sensors, one on the evaporator the other in question is behind front bumper, external.

 

[Trickster]

Clearly you are not, there are Two different sensors, one on the evaporator the other in question is behind front bumper, external.

Lol, is it that obvious?

 

[Trickster]

The thing that confuses me is the "50 degrees Fahrenheit or 10 degrees Celsius" statement. 10degC is 18degF, not 50!

@ASH8 is the sensor on the CX50 visible without any (or too much) disassembly, so we can check the lot/date number ourselves?

I sure hope your not an accountant.🤣

And though I am not a rocket scientist, I am a Canadian where we have to convert everything to imperial or US measurements. 🤔

 

[RedBaron]

I sure hope your not an accountant.🤣

And though I am not a rocket scientist, I am a Canadian where we have to convert everything to imperial or US measurements. 🤔

Clearly you are no rocket scientist nor a mathematician. The text says: "can be out by as much as 50 degrees Fahrenheit or 10 degrees Celsius". It's not talking about an absolute temperature value, but a differential conversion. (e.g. it reads 20degC when it is actually 30degC, or 68degF when it is actually 86degF, etc)

 

[Trickster]

10degC is 18degF, not 50!

You said the above.
What am I missing?
10C is not 18F.

No I am not a mathematician just a confused CX 50 owner.

I suppose the statement by using both Fahrenheit and Celsius is the culprit.

Please explain further, without pointing out any other skills I may not have.

But I have stayed at a Holiday Inn.🤣

 

[RedBaron]

First, understand that we are talking about an ERROR in the reported temperature by the sensor. In other words, a difference between what the temperature actually is vs. what the sensor reports the temperature as. Let's paraphrase your example: Say the outside temperature is 10degC, and this (as you said) is the same as 50degF. But now this bad sensor reports the temperature as 10 degrees (C) lower, or 0degC (i.e. invalid by 10-0 = -10degC). Now, as you know, 0degC (freezing) is equivalent to 32degF. So, the equivalent difference (the invalid reading) in Fahrenheit is 32-50 = -18degF.

To put it another way, a delta of 10degC is the same as a delta of 18degF.

The corrected sentence in the TSB should read: "The small external Sensor located behind Front Bumper can be out by as much as 18 degrees Fahrenheit or 10 degrees Celsius (under reading) meaning Temperatures outside of car are physically way hotter than what the instrument reading (from Sensor) says it is resulting in the cars AC's not cooling down inside cabin as it should"

 

[Trickster]

First, understand that we are talking about an ERROR in the reported temperature by the sensor. In other words, a difference between what the temperature actually is vs. what the sensor reports the temperature as. Let's paraphrase your example: Say the outside temperature is 10degC, and this (as you said) is the same as 50degF. But now this bad sensor reports the temperature as 10 degrees (C) lower, or 0degC (i.e. invalid by 10-0 = -10degC). Now, as you know, 0degC (freezing) is equivalent to 32degF. So, the equivalent difference (the invalid reading) in Fahrenheit is 32-50 = -18degF.

Thus, a delta of 10degC is the same as a delta of 18degF.

The corrected sentence in the TSB should read: "The small external Sensor located behind Front Bumper can be out by as much as 18 degrees Fahrenheit or 10 degrees Celsius (under reading) meaning Temperatures outside of car are physically way hotter than what the instrument reading (from Sensor) says it is resulting in the cars AC's not cooling down inside cabin as it should"

Now it all comes together. Thank you for the thorough explanation.
Thought I was either losing my mind or about to get into a pissing match about temperature conversion.🤣
✌

 

[Nzoka]

Clearly you are not, there are Two different sensors, one on the evaporator the other in question is behind front bumper, external.

Do you know which sensor is used to display the outside temperature seen in the speedometer display?

 

[ASH8]

Do you know which sensor is used to display the outside temperature seen in the speedometer display?

It is this sensor in question, is located outside behind front bumper cover which must be removed to access. If it is showing wrong temps outside it may need replacing.

 

[Nzoka]

It is this sensor in question, is located outside behind front bumper cover which must be removed to access. If it is showing wrong temps outside it may need replacing.

Thanks