Have had a number of issues with the system (realizing that what I call system, people smarter than me probably won’t ). Wonder what steps you would take/suggest at this point?

Bought new in May 2019 in PNW and now lives in AZ as of May 2021.

issues/symptons

Blower motor is loud. Mechanically clicking is best I can describe it. Some days are better than others. It does seem to get louder at higher fan speeds but still has a drone or hum low as well.

Airflow is inconsistent at times. it will blow as I would expect on highest fan setting and then others times it significantly reduced (auto temp off, fan at highest setting) happened for both cold and hot. In my eyes there is no rhyme or reason as to it happens when X is occurring. It’s intermittent. Was blowing well yesterday. The day before it was “light”. Sounds at times like it’s struggling to push air.

The cabin ac control panel will be on and the auto temp control moving the fan speed up but nothing is happening fan wise or forced air coming from the vents. Again both hot and cold. This is on rare side of occurrence. First happened back in late 2021 and then last week.

treatments

Mazda has replaced the blower motor 3 times. 12/2021, 9/2022, 9/2024. (Or at least said they did)

They have also replaced the control module/resistor (OEM part K124-61-765) 9/2024.

It worked well for 7-9 months or so if I had to guess after the 9/24 interaction then degraded, never went back because of life and other excuses.

I’m guessing they are interconnected and quite possibly an a contributing factor as my cabin filter replacement history hasn’t been great.

last week I replaced the filter, pulled the blower motor checking for obstructions and blew it out with compressed air. Cleaned the harness connections with 91 iso alcohol (ChatGPT recommendation). The next few days it worked well but has reverted. The cabin ac control symptom I mentioned above happened after this. I tried turning off the HVAC system and back on and that’s when it happened. Doing this can sometimes help the air flow and noise issue.

thanks for any suggestions, thoughts or tips.

 

Don't know but perhaps a good scantool can operate the hvac system and do diagnosis.

 

Definitely would follow this. Also check fuses in the engine bay as well as wires that look exposed or chewed through. Just for the heck of it I'd also get the battery tested too since that can cause weird electrical gremlins.

 

Current information on your Mazda is generally useful and helpful when asking service-related questions. It reads that whoever has been working on your Mazda is reading past service information instead of staring a better approach to your issue. Because it was not happening during the first couple years of service you can rule out rodent or wiring damage and the battery. But any issue related to a system that needs battery power as noted by another member it is always advisable to first get your battery load tested regardless of its age.

My advise if you are out of WARRANTY is to find a specific Air-condition and heating Automotive service in your area. At least these types of service shops are trained in servicing HVAC systems. Or look for an ASE certifide service shop.
Or because this problem was service under Mazda warranty you can try to see if Mazda will still assist your problem. Hopefully all your service information was entered by the dealership in your VIN service history. Which includes if they did in fact change your blower motor and other parts.

 

I, too, would start at a Mazda dealer. With the last repair in 9/24 it hasn't been that long. Maybe they would goodwill the repair (was the last fix under warranty?) Your issue is certainly not very common. I have read about blower motor issues in a few threads, but typically a new motor solves it. As you have had 3 blower motors since 19, it makes me wonder if something else is to blame.

How many miles are on your car?

 

The one thing that is important is that the OP had 3 replacement blower motors. That is not statically possible. There are so many variable reason why and it would be almost the same as buying a lotto ticket for the big win.
Either there is missing service information (often the case when a member authors a thread) or something was badly missing from the several people that worked on the Mazda. Another slightly unusual event unless the exact same people worked on the Mazda every time!

I would be careful about suggesting "GOODWILL" service labor until you know the exact details of the service. If out of warranty most are 90 days labor and whatever the warranty replacement is on the exact part used. If OEM there is less then aftermarket for a part warranty.

 

In well over 50 years working in the trade I have never replaced a blower motor. Dropping resistors and switches yes but the motors seem super reliable so 3? I really question that.

 

That's pretty good. A bit unusual but hey if you say its so I believe you.


We replace a damaged blower motor server during summer months and few during winter months. Most of them are pre cabin filter model vehicles and the other are from owners that seem to think they never need to change their cabin filter.

I changed mine in my Mazda 7 moths after I bought my Mazda new. I wanted one that actually had some serious CFM. The cage pushes more air then then any factory Mazda blower. The tradeoff is it is noticeable sound on max blower speed. but let me tell you during the summer when it 105-112F outside and you get into the car it only takes about 5 minutes or less and you feel very cool.....52F KOOL .... LOL

 

I had a blower motor replaced on my 2011 Tacoma before the 36k warranty expired. It started ticking (apparently pretty common in that gen of Tacoma) and they swapped it out under warranty. It didn't recur in the 60k miles I had the truck afterwards.