Air Conditioning Problem

[Alpha Wolf]

Driving back from Sacramento last weekend in 100 deg heat. We were forced to stop in heavy traffic. Then just when we needed the a/c the most it just switched itself off and would not come on. Just started blowing hot underhood air that was hotter than the outside temp

Then after we started moving again, it turned itself back on again.

Has anyone else experienced this? Does anyone know what the cause is and how to fix this so it will not quit on me?

 

[mikey1981]

i thought i was nuts. happens daily in my loaner mazda 6. At a stop, the ac switches off. i just thought it was broke cuz it was a loaner.

 

[Mazda Lover]

Most likely the engine was getting hot so it went into protection mode. However, if it did this to me I'd be PO'd. The A/C in general seems to be weak in these things then to have it shut off on you? Seems like poor engineering to me.

 

[erhayes]

In very high humidity you can get coil freeze-up? and the compressor will shut down until things warn up. I don't know if this is the cause but, many AC systems have this issue.

 

[1Sleepy93]

Haven't had any issues yet but we'll see in a few weeks when we take it on a road trip to Colorado Springs.

 

[Alpha Wolf]

In very high humidity you can get coil freeze-up? and the compressor will shut down until things warn up. I don't know if this is the cause but, many AC systems have this issue.

Sacramento valley is extremely dry.... Read no humidity to speak of.

While it was around 100 degrees The engine did not seem hot at all. The engine temp gauge never moved above its normal temp.

I will be taking it to the dealer for a nice b**** session...(strike)

I don't know what can be done if it is some stupid feature engineered into it.

 

[Mazda3]

No problems here. My a/c blows so cold you have to turn it down.

 

[erhayes]

Talking politely but firmly usually gets the good response where bitching gets you the same b****y attitude. Just my observations after many a year.

 

[Brian MP5T]

The compressor is engine driven, If you are stopped, the compressor is rotating much slower than normal. You might find that it will run hotter stopped..

It's not a Refirgerator, It's a car.

 

[Brian MP5T]

No problems here. My a/c blows so cold you have to turn it down.

"Canada" is not Sacramento...

 

[Mazda3]

"Canada" is not Sacramento...

No, but it is 90 degrees+ here this week. The Mazda 3 A/C lags a little when it gets this hot, but the CX-7 has no problems, so far its seems to be a better set-up.

 

[Brian MP5T]

Unless you are parked in traffic and your car is on fire, I still feel that the conditions are not the same.

 

[Zoom49]

We were forced to stop in heavy traffic. Then just when we needed the a/c the most it just switched itself off and would not come on.
Then after we started moving again, it turned itself back on again.
QUOTE]
The A/C depends on air flow through the condenser to remove heat. This is accomplished by ram air through the vehicle grill when the vehicle is in motion. When the vehicle is stopped the air flow through the condenser is accomplished by a 12 volt fan. If this fan is not in operation, then the compressor will shut off due to high pressure. When you start moving again and get air flow across the condenser the compressor will start again. Check and see if the A/C condenser fan is running with a cold engine and the A/C on.
Also found this TSB http://www.mstore2000.com/PDF_Files/07-004-06-1700.pdf
Does your vin fall in this range?

 

[Alpha Wolf]

Just to clear up a few points..

I am an Engineer and know how refrigeration units work.
I have owned cars for over 30 years. All but my 70 Beetle and 77 Nova had A/C.

Yes ram air increases the a/c units ability to cool.
Yes we were stopped.

However here are the reasons for my complaint. No car I have owned has ever "turned the a/c off" when I needed it, even in hours of stop and go traffic.

Yes some cars need to be moving to get the a/c really cold. My wifes Geo is like this, but even then it is still cool air blowing in when stopped in traffic for hours. My wifes new beetle would positively freeze you out of the car within 30 sec of turning the a/c on without ever moving. My Trans Am and C2500 pickup would both freeze you out and again, their a/c would never "TURN OFF". My wifes current car a Subaru BAJA turbo also will freeze you out driving under similar conditions

The CX7's a/c turned off and then went one worse. It started blowing heated engine air in the car which was noticeably hotter than the 100 deg outside air making a bad situation worse.

The a/c in all other vehicles I have owned has never once turned itself off under any situations. The a/c in all other vehicless I have owned have never started blowing Very Hot air instead of cold when set to max on a hot day.

The CX7's a/c turned off, quit while stopped. Had it merely not been as cold while stopped I could understand that as the Geo's does that as it's system really needs ram air to function to max cold. That was not the case here. The system stopped working 100% not merely a few degrees drop in temperature.

Since GM, Subaru, VW and Suzuki all have a/c units that do not turn off on their own there is no excuse for my Mazda a/c to do so.

Up until this trip it had never done this and it was always quite cold when turned up and I have no complaints.

It seems there is either a weak part that gets over heated when stopped and thus turns the system off, or there is a deliberate design feature to do so. either way this needs to be rectified as anyone who lives in hot weather and heavy traffic will never buy a Mazda.

(drive2)




Since a

 

[Brian MP5T]

Just to clear up a few points..

I am an Engineer and know how refrigeration units work.
I have owned cars for over 30 years. All but my 70 Beetle and 77 Nova had A/C.

Yes ram air increases the a/c units ability to cool.
Yes we were stopped......

So let me clear something up as well... Your tone makes you sound like an asshole. We are suggesting things to try to help you, If your so AWESOME, why not work it out all by yourself.

I'm done trying to help you..

Unsubscribing.

 

[wongster]

when we went to vegas last weekend.. we rented a caravan.. and it was samething too.. when it was not moving in movin traffic. the ac was not working and was blowing hot air, but when we were moving.. thats when i got colder.. we find that kinda annoying... but my cx-7 in canada never had that problem.. p rob because we dont have the same conditions in toronto compared to vegas or other hot areas in states

 

[Alpha Wolf]

So let me clear something up as well... Your tone makes you sound like an asshole. We are suggesting things to try to help you, If your so AWESOME, why not work it out all by yourself.

I'm done trying to help you..

Unsubscribing.

First your name calling aside, which is a bit juvenile by the way, I am not pleased by having my new car's a/c stop working when it is needed the most. Not less cold, we are talking about air blowing out significantly hotter than the 100deg temp outside the car.

As I am not typing in caps or using foul language one does wonder how you can know what my tone is other than not pleased about this. I am sorry if listing a problem with my Mazda CX7 and the fact I am not happy about said problem is deemed "b****y". How should one feel? (dunno) Extremely elated that my car fails to function properly and up to my expectations?(dunno)

How can turning the a/c on and getting extremely hot air coming out be normal or acceptable to anyone? (dunno) I guess if you never drive anywhere with traffic and heat it could be.

Should I feel extremely happy the a/c on my new car cannot be counted on when needed the most? When our Subaru Baja turbo under the same conditions blows extremely cold air out and cost thousands less? Which, my wife now reminds me of on a daily basis and gets quite a chuckle out of it when doing so.

Call me over demanding, but in 30+ years of driving and owning a number of cars over that period from various manufacturers all of whom have been driven over that exact same route on as hot or hotter days and none shut their a/c off and started blowing hot air.

If this is a design feature, it is a band aid and indicates some failure in engineering either with the cooling system of the car or of the a/c system. Though as I have stated the temp gauge did not move a bit and was still down 1/4 below the half way mark toward the C. So it would not appear to be due to the engine overheating. But that does not eliminate the possibility that this is something done to prevent overheating. Thus, if that is the case and just not some problem isolated to my particular car, others will be experiencing this and if Mazda has no fix this will negatively impact other owners of CX7s. So my post was partially to see if anyone else had experienced this and if so were they able to get it fixed or were they forced to just live with it. Or if any Tech Bulletins were out covering this problem.

 

[Alpha Wolf]

when we went to vegas last weekend.. we rented a caravan.. and it was samething too.. when it was not moving in movin traffic. the ac was not working and was blowing hot air, but when we were moving.. thats when i got colder.. we find that kinda annoying... but my cx-7 in canada never had that problem.. p rob because we dont have the same conditions in toronto compared to vegas or other hot areas in states

Man I hope this is not something industry wide! Yikes... (confused)

I just hope they find something amiss at the dealer and it can be fixed and is limited to just my car not to all CX7s out there..

I will have to wait and see...

 

[mogulman]

Yeah..please let us know what you find...

Maybe there is some kind of leak in the refrigerant or the level is just low. This could cause the compressor to intermittently turn on and off.

We've been having heat of about 95-99 hear in Colorado. I haven't noticed anything like what you are saying. Although the AC does seem weak sometimes.

 

[Alpha Wolf]

Yeah..please let us know what you find...

Maybe there is some kind of leak in the refrigerant or the level is just low. This could cause the compressor to intermittently turn on and off.

We've been having heat of about 95-99 hear in Colorado. I haven't noticed anything like what you are saying. Although the AC does seem weak sometimes.

I will post what I find out.

I am looking to see if any TSBs cover this but had not found any yet.

This was the first time we were in hot weather and had to remain stopped for any length of time. Like I said, prior to this we had not experienced this before...