CX9-2012: Air Conditioning Problem (Driver Side not cooling)

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Mazda CX9, 2012, Full Option
- Cooling is less at driver side but passenger side and rear side works perfect.
- In the morning and in the evening (when outside temperature is less), driver side cooling is also better, but still less than passenger side.
- In the afternoon, if the car is parked outside in the sun and outside temperature is high. The Driver side AC is hot and gives no cooling, but passenger side works well. But when car moves at speed, drivers side AC gets slightly better. Also when stops in high temperature, only driver's side AC gets hot. Also, while the car is running in the high outside temperature and Rear AC turn off, the AC gets hot.
- 3 months back, on the same complain, Mazda dealer had Top-up the AC Gas, but it had no impact and no improvement to the AC. So it is not the Gas issue.
- Mazda has suggested to replace the Evaporator that is costing USD 1,000/-
- Need advice from members, does it really looks an Evaporator issue or may be something else like controls or sensor problem, possible malfunctioning of servo motors, actuator, air mixing flapper doors etc.
 
You are on the right track I think in that it certainly sounds like a mixing door in the instrument panel that is causing the issue. The real question is 'which one'? I cannot say for sure but if you do a more detailed search for those components that may help. I cannot believe that a dealer is saying it needs more work on the charge or the other exterior components when it is obviously blowing cold air in all but one spot.
 
- Cooling is less at driver side but passenger side and rear side works perfect.
- In the morning and in the evening (when outside temperature is less), driver side cooling is also better, but still less than passenger side.
- In the afternoon, if the car is parked outside in the sun and outside temperature is high. The Driver side AC is hot and gives no cooling, but passenger side works well. But when car moves at speed, drivers side AC gets slightly better. Also when stops in high temperature, only driver's side AC gets hot. Also, while the car is running in the high outside temperature and Rear AC turn off, the AC gets hot.
- 3 months back, on the same complain, Mazda dealer had Top-up the AC Gas, but it had no impact and no improvement to the AC. So it is not the Gas issue.
- Mazda has suggested to replace the Evaporator that is costing USD 1,000/-
- Need advice from members, does it really looks an Evaporator issue or may be something else like controls or sensor problem, possible malfunctioning of servo motors, actuator, air mixing flapper doors etc.
It happens when your refrigerant level is low. I had the same issue. After it was recharged it went back to normal. I have a small leak in the system so chances you are too.
 
The correct refrigerant charge in my 2017 CX9 is 750 grams of R-134a as shown on the sticker under the hood. The correct way to recharge is to remove all the refrigerant, then add back the specified amount. If there is a leak, then it needs to be found and fixed. I'm not sure why a partial charge would result in varied cooling on one side. A control problem seems more likely, perhaps the damper/mixer/flap. With a warm engine and the cooling set to max, try moving the temp control from full heat to full cold & back. You should feel a change in the air flow and hopefully an change in the temperature in the air coming out of the vent.

When you said, "Mazda has suggested to replace the Evaporator," was that just the service writer at the dealership? On anything where you can't actually see the source of the problem, be sure they always write the problem on the work order, not just the service writer's guess at how to fix it. If it isn't fixed, don't pay. You don't need to pay when the service writer guesses wrong. And, it might not be the evaporator that's leaking. It could be a 15 cent o-ring, still a lot of labor to get to it, but almost no parts cost.
 
Thanks all for the valuable advice. I will first try to recharge the gas and see the difference. I will give my feedback.

Great if some share his experience for replacing the evaporator, what were the symptoms and was that useful. My car running is just 62,000 KM. Is it common in CX9 to replace the evaporators this quick?

Thanks All, Syed
 
No it is not common. I had to recharge mine because I had a leak and my dealer wants $800 to fix it. The thing is that the leask is so small so I can charge it knce and it lasts a year before another charge. I am planning on fixing it eventually though and it is only a temporary solution. But I bet any money it is due to low level that you have different temperatures in different vents.
 
just a thought, the driver side heater core might be letting hot coolant in...Have it checked as well!

PS: Good to see another owner from Qatar!
 
Thanks all for the valuable advice. I will first try to recharge the gas and see the difference. I will give my feedback.

Great if some share his experience for replacing the evaporator, what were the symptoms and was that useful. My car running is just 62,000 KM. Is it common in CX9 to replace the evaporators this quick?

Thanks All, Syed
Syed did you end up recharging your ac? I bet it did the trick if you did recharge it
 
Yes I did and it worked well. Now my AC is very cold, all sides are balanced. My conclusion for the benefit of all is below:
- If driver side cooling is low, means there is a shortage of refrigerant.
- Shortage of refrigerant may be due to leak or may be reduced just over the period of time.
- Correct way to refill the refrigerant is to empty the system and fill the whole new cylinder, this will make sure that you have right levels.
- Most important is, Never trust a Mazda dealer (specially the one in Doha, National Car). When I first brought the car to them, they kept the car for 2 days, they said that they have checked the AC and refilled the refrigerant, it should be OK and if there any problem tell us. But they didn't do any thing. The AC was same. Second time I brought the car with same problem, they again kept the car for 2 days and said Evaporator to be replaced and quoted me $1000. Thanks God, I am saved and the issue is fixed in $30 only.
- About 4 weeks now, the AC is still good. This means, if there is a leak, it is not major. I am still keeping it on trial and see if it continue working well.

thanks, all
 
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