I own a 2004 RX 330 and I have a few questions about the AC. 1) in all my other cars I can get the AC to run and cool the car if im idling in a parking lot by simply raising the RPM with my foot to about 1500. AC goes on and cools off car. However, with the RX330 it does not click on even if I raise the RPM while the car is parked. However if I start driving, and the car is moving, it seems to go on right away. Is this the design? or is there something wrong with my car. Even If I drive with the RPM low, like 1200, the AC runs fine. But while sitting in a parking spot I have no AC and it still wont turn on if I rev it up to 2000 rpm?? I dont think any of my other cars did this. whats up with that?
Bruce

 

The fan should go on right away, possibly need a little bit to get the interior cooled down thou. I roll the window down to let out the heat from sitting at work. Tinting the windows really helps as well....I've had other vehicles that cool faster then this rx, but it does cool down after a bit of driving & then I find that I need to turn the fan speed down & the temp up some.......

 

Thanks for the reply. The core of my question is still there. Its not the fan. Fan works fine. Its the actual AC unit under my hood that is not clicking on when Im idling while parked. It seems to turn on when I start driving though. It seems not related to the RPM (which is weird in my estimation) and somehow more related to the movement of the wheels or car actually driving. strange huh?

 

Hi friend, Felix is correct and this IS the issue. lol

At idle when switching on the AC in MANUAL MODE with fan speed on high, both the condenser fan AND the compressor should come on together at the same time, always.

On our cars we have an "AC Amplifier" so it's much more complicated than meets the eye.
Not sure why the called it that but it's basically an micro controller based control module on the BEAN network that controls the AC,

This module takes inputs from all the sensors including ambient temp outside and cabin temp inside and evaporator core temp, refrigerant pressures, etc, etc and then turns the compressor & condenser fan on and off.

But one dead giveaway of an issue is if the condenser fan comes on but the AC compressor does not engage, so please confirm this first.

PS- when driving there is more airflow thru the condenser aka more sub-cooling.

 

To add, when inside the rx, I don't even hear the compressor cycle on/off, let alone the cooling fans.......

 

Aha, my bad. When "fan" was mentioned I thought we were talking about the fan blower that blows air inside the vehicle. Misunderstood. So, I am not sure the compressor fan is working and it was the actual compressor that appears to only come on when the car starts rolling. in my other cars the slight press on the gas pedal would cause the parked car to switch on the compressor and the AC would eventually start blowing cold air (not lukewarm ambient air)
How would I know if the compressor fan is working. can I have someone else inside the car and while parked get the rpms to 1500? In my other lexus rx 350 (2009) this does not happen. I can be sitting parked with the car idling and the AC blows cold air as if I was driving. This is why I suspect something isnt right with my 2004 rx330. Is there some kind of test or electrical test I could do that would help me figure out what is happening and why the car has to be rolling in order for the AC to get cold.
I have checked the freon pressures and they are normal.
Thanks for clarifying.

 

So does the interior fan work? Turn the ignition switch to the on postion & then see if the fan works on all the speeds, I belive 5 different fan speeds.

 

First thing I do is put gauges on it.
If the compressor is running you will see it in the pressures, no helpers are needed for this part.

If it is warm outside and the AC is in manual mode on MAX cool and the vent fans are on high you should be able to pop the hood and see the condenser fan running(passenger side) and see the compressor running by visually inspecting the compressor and also by looking at the pressures on the gauges.

If everything looks good at this point then it's time to grab a helper and have them rev the engine up to approx 1,200 rpm and see if the LOW side on the pressure gauge drops low and approaches zero psi- this means low on refrigerant -OR- whether the LOW side pressure shoots up and compressor disengages.

Also, on the gauges with hood up you may or may not hear the compressor cycling on and off while watching the pressures- let us know what you hear and see.

 

Thanks for the help. yes, the interior fan works just fine. It goes to all speeds and works perfectly. it works the same whether it is idling, or moving. It works on all different levels and speeds with the air conditioning on or off. With that said, I think I am starting to make progress as to my problem. I started looking at the two outside fans that are up against the radiator. There is a driver side and passenger side white fan that cools the engine and is electronically controlled. I happened to notice that when it clicked on only the driver side was working. I do not know if they are supposed to work in tandem, separately, or both linked together. However, I did note that the driver side fan would only click on when the car was about to overheat. Usually, neither of these fans are running. During my experimentation, with idling the car to check the air conditioner, the car started to get warm and the temperature gauge started going up. As it started to go up and got past the three-quarter mark almost up into the red bar (overheated) the one radiator fan on driver side clicked on for about five seconds and clicked off again. Something just didn't seem right. I would think it would run longer than that. I also would've expected both fans to operate simultaneously because the car was about overheat. With both of the white cooling fans off I walked over and carefully spun the white fan on the passenger side and it started to operate and caused the other fan on the driver side to click on as well. When that happened I also noticed that the air conditioning was getting cool and operating normally even though the car was idling and not driving. So I believe there is a connection with the cooling fans and air conditioning functioning. Now I have to figure out what is going on with my radiator fans and why it only worked when I spun it with my hand to get it going. I would also mention that after I spun it it ran very smooth and quietly as if there was nothing wrong with it. I am wondering if there is a loose connection somewhere in my spinning the fan manually made the connection reconnect and start functioning properly.
On another note with my air conditioning- I rechecked the pressures and it appears that when the air-conditioning is "on" the pressure is about 45 – 48 which is in the green zone. However (and this may be normal) when the air-conditioning clicks off the pressure goes way up into the red zone. I took some pictures and videos that I'm going to try to attach to make my descriptions a little bit more clear. If I am unsuccessful in attaching them I will try to attach them to another message.
It's great to have a community of people to help solve Lexus issues because I am beginning to realize that I don't understand much of what I thought I did understand.

With AC running

With AC off

 

Ok Brucecav, you've us a lot of good info so I'll chip in some ideas!

Cool deal!

Not good, you are in danger of blowing your engine or head gasket the next time the temp approaches red and your radiator fan(on driver side) decides not to work.
With a scanner you can watch the live engine temp data.
You should witness the fan(driver side) will come on approx 206F and cut off at 212F.

Disclaimer, going off memory so I'll have to look it up unless someone has the exact temps but the point is it should always kick on at the same temp and cut off at the same temp and the temp gauge should be in normal range.
Problem is it looks like it's waiting until the temp is way too high to turn on.

Yes sir, you are correct.
It should run continuously until the goal is accomplished and it cools to normal running temp.

It would make sense but I don't think it does and I'm too chicken to run my engine that hot to find out if it will run dual fans based on overheating engine. lol
Normally, the radiator fan on driver side is the one that comes on and off as needed and depends on the coolant temp.
The fan on the passenger side is the condenser fan and only comes on when the AC compressor is running- if everything is working properly.

Yeah, you have something weird going on there. lol
Let us know what you find out. Sounds like one of the fans may be pulling too much start up current maybe or bad ground or connector, or something. so you definitely have something going on.
What bothers me the most is the driver side fan not coming on when it should and this fan turns on and off based on coolant temp.

Looks ok and I can tell the compressor is running from your gauge pics and you have ample refrigerant in the system at this rpm.
Whether the refrigerant level needs tweeked for best performance can be done later but this looks ok for now.

This looks ok
When the compressor is off, the low side pressure will rise and the high side will fall as they attempt to balance out.

 

Thanks for all the comments and help. I need to do some data gathering as to the actual engine/coolant temp before fan clicks on and also electrical research to find out why the fan turns on when I spin it and remains on. One thing I was pondering, when I spin the passenger-side fan, the other fan will then turn on as well. This must be some sort of electrical failure and somehow my spinning the fan reduces the current needed to get it going. I might have to pull my voltmeter out and check some wires. I will also check the electrical plugs and connections. Luckily the fans both spin very quietly and smoothly once they get going. Anyone else have anything to chime in on this strange scenario? Is there a specific thermostat switch or temperature switch somewhere easy to access that will signal the fans to turn on? If there is a specific accessible part, that part may be what's failing.
I have a blue driver which is supposed to give me live data on several operations of the car. I haven't figured out how to use this thing yet but my goal is to look up how to get into live data information while my car is running so I can see engine and coolant temperatures and see if they line up with the gauge on the dashboard. Can someone please remind me of the normal temperature of coolant for healthy car? Also what is the temperature that is the yellow zone and what is the temperature that is danger zone?

 

Problem solved!!! All of your advice was correct. The air conditioning problem had everything to do with the 2 fans at the radiator. Turns out that 1 of the fans near the air conditioner would only start turning if I jumpstarted it with my finger. I connected 12 V directly to the fan and it did not start. Same scenario. With 12 V directly connected to the fan I had to jumpstarted with my finger and that it would run.
After a $95 investment on eBay I received a whole new fan unit including both fans and motors in a frame. Installed it yesterday and everything is working great. Air conditioning is now working when idling. Also my average antifreeze temp. Is now 175 – 185 and before it was 175 to 225...Yikes.
Thanks for everyone's input and I'm really glad I have AC again!!
One little tip- getting the plastic tube pushed back into the underside of airbox was no joke. That was a little taste of torture, and finally had remove the battery. A few foul words were used at that point. But it's all back together and running great.

 

Good job Brucecav.

Thank you for following up and posting your fix.
It's always nice when members follow up and I'm sure your contribution will help others in the future.

PS- I have a guess on why your AC would start working when you drove very slow. Since the fan blades requires very little inertia to start spinning, I'm guessing when you were idling down the road it was just enough airflow across the pitched blades to help get them to spin- basically giving it a boost like you did with your finger. Just ideas.