dfwlexusES

The AC in my 02 ES blows nice and cold, as long as I am moving! Once I stop at a red light, warm(er) air begins to blow. Light turns green.....cold again...

I have had a few mechanics look at this, and it seems that everyone has a different idea. One says that 1 of the 2 fans near the radiator stops, so the air turns warm. Another says, no, that's normal, one fan is for AC and the other to cool the radiator...

Another said that it is the level of RS32a in the system...the other than says no, it cannot be that, since it does blow cold when moving.

Yet another mechanic did a check on all of the fuses and relays (which were all apparently working, and said, it must be the compressor.....

Feel like I am playing Russian Roulette on the diagnosis.....and certainly do not want to throw $$ at it trying everything possible...

Has anyone else had this particular experience, or might know exactly what might be causing this?

LeX2K

Someone with a 2002+ ES can confirm, I believe both fans should run when the A/C compressor is on so check for that. A competent shop with proper equipment can easily check the refrigerant level/charge.

dfwlexusES

Refrigerant level is good, I have already had that checked. So......if (and that's a big if) BOTH fans should run......what is causing the fan on the passenger side to stop running whenever the car is at a light?

crwys

It's a long shot but voltage drops when you are idling due to low rpms. I'm pretty sure both fans should be running when the ac is on, they do on my 99. Maybe the fan isn't running due low voltage output from the battery/alternator and that's causing the ac to blow warm.
easy way to test this is have someone look at the fans while you are in park and give the car gas, they can measure the voltage before and after and/or look at the fans to see if they both run. You can also see if the ac starts to blow colder if you give the car a little gas while in park.

Oro

Do you get a blinking climate control light and have you replaced the a/c relay in the engine fuse box with the updated unit? The OE cc relay in the 02+ models is known to fail and has been updated.

dfwlexusES

CRWYS - Yes!! Both fans will start when I give it a little gas and it blows cold!!
ORO - I did replace a relay last year....was hoping that it would fix the issue. Is it possible that I replaced it with a new unit but the old version? How can I distinguish? Is there a different part# for the new version? Does anyone know what it is??

crwys

That's awesome, good news, making some progress finally lol. So next step would be to measure the voltage at idle to see if it's too low. I'm not sure if that OE cc relay has anything to do this or not so you'll have to research that, sorry.

If its not too low or you aren't noticing any dimming headlights or anything like that I wouldn't think it's your alternator, maybe also check the voltage on the fan plug that isn't running.

dfwlexusES

Oro

crwys

Check this out.
https://www.autobatteries.com/en-us/...ge-and-testing

I would also test the voltage on the connector that plugs into the fan that you have having trouble with. There is 2 terminals on the inside of the plug, you just touch the 2 while the car is running with the A/C. Same for when you test your voltage on your battery/alternator.

If your voltage is good on both your Battery/alternator and fan connector I would look into testing your fan motor and/or replacing it.

dfwlexusES