lexus114

i have noticed ever since i got my 15 rx that on hot days when i get in, and start it up. there is a pretty long delay before the a/c starts blowing. anyone else notice this? kinda stinks when its hot out and the inside of the car is even hotter? all i know for sure is my 01, and 05`s used to come on almost instantly, so just curious if this is just the way its supposed to be on the 15.

harleybob

I agree I have a 2015 Lexus RX 350 on a warm day takes about 15 to 20 seconds before the air starts blowing and at that point is not really blowing full speed and if I hit the AUTO button I see I only have 3 bars on the fan speed very rare does it go all the way up - be extremely hot in the car to do that I just had a 5000 mile checkup done they gave me the keys to two brand new Lexus is I'm a lot they both have the same thing as mine normal unfortunately

Bucky44

I have the same thing on my 2015.

justin1203

I have a '10 RX350;

Does the same.

I think it's part of the programming, so it doesn't just blast hot air at you.

None of my old cars where you could instantly turn the air speed to high would push out cold air.

BertL

...and FWIW, my MBZ does something similar. Not everything comes on immediately. It seems in both it and my RX there is some sort of sequence the vehicle's computer follows to cycle the various subsystems and components on. I guess it has never bothered me, as I'm used to booting computers of all sorts and not having everything come on immediately, like I expect a light switch in my home to do.

For the OP with really hot weather... A couple alternatives to perhaps help. Both have varying degrees of pros and cons I suspect everyone will jump on with their opinions

1. If it's not raining and you'll be back in a reasonable amount of time, you could leave the moonroof tilted open. I find that helps quite a bit when I'm out and about in the heat of the summer. The RX will still lock and have the security system on when you lock the doors via your normal routine. (FWIW, I like the moonroof tilting approach vs the "slide it back" variety if I'm locking and leaving my car for a short time on a really hot day, as it's harder to have an errant bird bomb your interior or some maniac throw trash into your vehicle while you're away.)
2. As you walk towards your RX, press and hold the unlock button on your FOB. Your windows and moonroof will open as you approach giving you a few seconds headstart getting the heat out of your RX before you jump in. You'll learn how far away you can be after awhile -- it's not that far, but is better than nothing for those that want to use the feature I suppose. Fresh batteries seem to help too.

yardie876

Not sure on the RX but the GS has an option where you can opt to have the fan speed gradually increase or decrease, or hit min/max immediately. The fact that it takes a while is also programmed as such to inhibit the blast of hot air like others mentioned.

novaman

I believe that the reason is that when the RX is first started and is hot inside the compressor starts and the blower is delayed so the evaporator can get a little bit cold before the blower starts(less hot air blowing.)Nevertheless, the blower may only start on low to med so to allow the air to move over the evaporator to remove more latent heat (dehumidify.) It's the same principle that home air conditioning works in that a lower fan speed takes out more humidity then a fast fan speed. Then after a couple minutes or so the blower or fan speed increases so sensible heat is removed.

novaman

NateJG

What's a warm day like (I'm in Michigan)?

<Grin>

lexus114

thank you for your replies guys. i appreciate all of them