My wife and I have spent the last week researching the CX9 as a replacement for our 2013 Honda Pilot. We settled on a pearl white Signature with the parchment interior and had driven it twice. I'm in Las Vegas and daytime temps are in the mid-100's right now. On the first two drives both of us noticed the cabin never got completely cooled off even with the ventilated seats turned on. The test drives lasted about 15 minutes and included about 10 miles of highway driving, which should have been plenty to cool down the refrigerant. We had negotiated a pretty good deal on the vehicle and were ready to go back and buy it last night but I told the salesman I wanted to measure the AC temp at the vents on another drive to make sure it was working correctly. I bought an AC thermometer locally and, for reference, measured the dash temp of my Honda Pilot and Toyota Tundra. The Pilot, after driving on city streets for less than 10 minutes, was around 44* in motion and got up to 48* at stoplights. The Tundra took a bit longer to cool down but in motion was around 41* and went up to about 46* at lights. Both cars were measured at the center dash vents. On our 3rd test drive last night the CX9 went down to 58* on the highway after about 10 minutes of driving and would go all the way up to 65* at stoplights. Once again, the cabin never really cooled off and felt comfortable. This was at around 6 PM land the outdoor temp was around 105*. We tested another CX9 on the dealers lot and it never got colder than 70* at dash vent while idling.

Frankly, we are really bummed that the CX9 has such a weak A/C system. That car checked all the right boxes for us right now - perfect size, incredible interior, smooth and quiet for road trips. But, for daily use driving around Las Vegas I'm worried the A/C would be ineffective on short trips and leave us uncomfortable and frustrated. I guess I'm looking for feedback from anyone that lives in the southwest about how their CX9 performs in the hot summer and - more importantly - if anyone has been able to boost the A/C performance somehow.

 

I would ask the salesman to discuss this with the service manager...while you listen. One possibility is that the heat controls are misadjusted and some hot air is mixing with cold air, or maybe the recirc & fresh air dampers are misadjusted. It will probably require a tech to remove the dash to make these corrections. You could try for a contingent purchase deal...if they can get the vent temp down to--pick your number, maybe 45° while driving--then the deal goes through. Don't buy until it works the way you want. An alternative test is for the cabin temperature away from vents and windows gets down to, what?, 75°, then you'll buy the car. That's what you really want, a comfortable cabin, not chilly vents.

We know that the CX-9 AC isn't the strongest. I'd also like to hear from others in the hot southwest.

 

I'm in S. Florida. Bad A/C is not an option. My CX-9 does very very well in 95 degree temps. No complaints here and I know bad AC.

 

My 2018 Signature A/C is erratic. I tried adding some freon at 100 F ambient. The A/C low side pressure was about 50 psi. but a/c still was erratic. Going to call it in for warranty to see if its the compressor fan clutch.

 

My guess is that it's not the clutch. My guess is that it's the fan clutch relay. It's a simple DIY if you want to try. The relay looks like a large fuse and can usually be found in the engine compartment along with other relays and fuses. In a pinch...it's worth a quick look. Good luck.

 

Too much refrigerant diminishes the cooling (Freon® hasn't been used in years). The excess refrigerant is held in the bottom of the condenser reducing the condenser's ability to throw off heat. The correct amount of refrigerant by weight is just right. More is not better. I haven't paid attention on these cars, but usually one can hear when the compressor clutch activates and deactivates. If the compressor isn't turning when it should be, there might be a problem in the clutch system--the clutch itself or the relay or something else. In any case a qualified tech needs to check it.

 

I'm thinking it might be the blend door actuator for the A/C.

I bought my CX-9 back in April of this year. Had to start using the A/C in June.
When the CX-9 is sitting in the sun for a few hours getting it cooled down takes a while.
I was out of town and went to Autozone and bought a freon bottle with gauge. The low pressure indicated it could use some freon.
I added a little bit at a time, monitoring the pressure and quickly the pressure spiked.
I then thought to let some freon out from the low side while the engine was running using the hose from the bottle. I noticed a bit of air coming out and little freon.
I'm wondering if the system had air in it?
Last week I used my A/C manifold gauge and read 36 psi on low side and 227 psi on high side with outside temperature being 92F.
This seemed reasonable so yesterday I put a thermometer in the A/C vents as I ran errands. I noticed the side vents fluctuating from 45 to 48F while the center vent hovered around 43.5 - 45 F.

This seems to indicate to me that the blend door for the side vents isn't shutting all the way.