HVAC FAN SPEED VARIATION

[BlownGP]

Yeah, that looks like the same part from Advance auto.

But looking at the pic. If it's by the blower motor, then it should be right behind the glove box
Guess I might take a look this weekend.

Sponsored

 

[Deleted member 35786]

Yeah, that looks like the same part from Advance auto.

But looking at the pic. If it's by the blower motor, then it should be right behind the glove box
Guess I might take a look this weekend.

There is another thread where someone changed it out and it did not fix the fan speed issue.. sooo.. dunno. For $31 why not give it a try I suppose.

 

[Dmesser92]

I bought my '17 with 7k miles on it and noticed this on the drive home from the dealership. Mine will slow, get back to speed, slow down, and sometimes almost cuts out for a brief moment. I've noticed when I'm on a call the fan speed decreases but that is by design. This is a technical issue somewhere in the system. I took it to my dealer and they claimed they couldn't reproduce the problem. They said wait until it becomes more consistent and bring it back. I'm under warranty until September of 2020 so there's time. With all the A/C issues these cars have this doesn't make me feel good about the situation.

 

[BlownGP]

I bought my '17 with 7k miles on it and noticed this on the drive home from the dealership. Mine will slow, get back to speed, slow down, and sometimes almost cuts out for a brief moment. I've noticed when I'm on a call the fan speed decreases but that is by design. This is a technical issue somewhere in the system. I took it to my dealer and they claimed they couldn't reproduce the problem. They said wait until it becomes more consistent and bring it back. I'm under warranty until September of 2020 so there's time. With all the A/C issues these cars have this doesn't make me feel good about the situation.

Typical dealership.

I hope you have no more issues, but it would be nice to see what the dealership does if it happens more consistent.

 

[coreystang]

My 2015 pp is doing the same thing. The AC blows strong and cold. But when sitting it will surge up for 20 seconds then drop back down. RPM's raise and drop too.

 

[Emilbadal]

Although it might be annoying to some but it's kinda funny. I had this issue from the beginning . I have a '16 V6 and as I was reading through this thread, I remembered that on couple of occasions I have actually noticed the fan speed LED indicators (only on base) spazzing out and blinking with the change in the fan speed on its own. The problem still exist after I have done the Sync3 upgrade.

 

[BlownGP]

So, have a update for the issues I was having.

I finally got around to buying a new OEM blower motor resistor. Swapped it out and it fixed my problems. I was shocked.
Now the only issue I have is the passenger side vents are blowing hot air. I had to take a blend door off to get a better access to the resistor and I guess it needs to be reset or something.

Anyways. It's nice knowing your A/C will come on now or the fan speed will change when you want to change it. lol

 

[Tobey]

What's the part number of your replacement? I'm wondering if it's been revised. I replaced mine a year or so ago, and it didn't fix anything. Mine only does it in the summer. And I live in Houston, so I use the AC year round.

This stupid behavior generally starts in May/June, and will continue through October. Then it will work normally for the next 6 months. It makes me think it is affected by sitting in the heat. But those cooling fins stick up in the air flow, so I don't really know.

 

[BlownGP]

This is it right here.
https://www.ebay.com/itm/FORD-OEM-1...e=STRK:MEBIDX:IT&_trksid=p2060353.m2749.l2649

I didn't think it was going to work either. Guess they have some bad batches of them.

 

[Dana Pants]

I always assumed we have a “smart alternator” that changes the voltage level based on driving condition. (This is a thing to save fuel). Changing voltage would change fan motor speed.

I haven’t looked at voltage to confirm, but it’s a good theory.

 

[BlownGP]

I always assumed we have a “smart alternator” that changes the voltage level based on driving condition. (This is a thing to save fuel). Changing voltage would change fan motor speed.

I haven’t looked at voltage to confirm, but it’s a good theory.

These cars do have that. Something I learned when I got my Ngauge and was wondering why the voltage would drop to 12v every once in a while. Freaked me out. lol

 

[Tobey]

I always assumed we have a “smart alternator” that changes the voltage level based on driving condition. (This is a thing to save fuel). Changing voltage would change fan motor speed.

I haven’t looked at voltage to confirm, but it’s a good theory.

Good theory, but I've watched the voltage reading and it doesn't seem to have any impact on the blower motor speed.

 

[Tobey]

This is it right here.
https://www.ebay.com/itm/FORD-OEM-15-17-Mustang-Control-Module-FR3Z19E624A/223702019951?ssPageName=STRK:MEBIDX:IT&_trksid=p2060353.m2749.l2649

I didn't think it was going to work either. Guess they have some bad batches of them.

That's an updated part number from when I replaced mine last year. I just ordered it; willing to try a 2nd time. It's driving me crazy right now.

Old: FR3B 19E624 AA
New: FR3Z 19E624 A

 

[BlownGP]

That's an updated part number from when I replaced mine last year. I just ordered it; willing to try a 2nd time. It's driving me crazy right now.

Old: FR3B 19E624 AA
New: FR3Z 19E624 A

That's good. Hope it works.

The number on my stock one I pulled out didn't match this new one. So I guess they updated them.

 

[coreystang]

That's an updated part number from when I replaced mine last year. I just ordered it; willing to try a 2nd time. It's driving me crazy right now.

Old: FR3B 19E624 AA
New: FR3Z 19E624 A

Keep us updated if that fixed the issue. It drives me crazy!

Sponsored