2006 Lx470 A/c Not Cooling In Auto

[Dagent]

Hello everyone

I took my 470 to the dealer for the drive shaft recall. After I got it back the memories and all settings were erased. Now the a/c only cools when set manually to Max Cold (below 65 degrees) it blows very cold air. When switched to auto it blows warm air and works at a low speed. The local dealer is telling me that it is low on freon and the system doesn't have any faulty codes. I'm not buying it. The level of freon affects the temperature of the air but shouldn't have to do with the operation of the system (I believe). I pressed the service writer to search for any technical service bulletins on this but he said there are none.

Does anybody have any ideas or suggestion that could help?

Thanks in advance

2006 LX470

58,000 miles original owner

[BlueVaporMist]

I have an idea. In the panel facing the drivers right knee there are several half inch vents recessed in the plastic molding. That is a temp sensor for the climate control. It likely got unplugged, loose, damaged, jossled, etc. Check that out or ask them to. Sounds like the system does not know the cabin temp.

[Dagent]

I picked up the truck today and they didn't charge me for the estimate.. I'm taking it to a friend to verify the freon level and if so I will add what's needed. I will also look for the sensor you are suggesting to ck it out.

I'll keep you posted.

Thanks so much

[Dagent]

Mr. BlueVaporMist

It has taken me a while since you last suggested to ck the cabin sensor. Today I finally did. I found the sensor connected but the white vacuum tube or hose was off (see attachment). I was hoping it be my problem. The sensor was not that dirty but I decided to blow it off with air pressure. I connected the hose and turned the A/c to auto but the same sympton. With 88 degrees outside I select the cabin temp to be 73 and it blows warm to hot air. By the way I cked the freon level and it is right on the money (hi and low)

I blocked the sensor assembly with my finger to feel for suction but I felt none. Where is the suction of that white tubing coming from? Is there a way to ck the sensor?

I had the cabin filters changed recently. Is there any connection from the blower side behind the filters or at it, that could had also gotten loose or blocked? Maybe a combination of two things.

I thank you for any advice.

[pj8708]

This area is out of my area of knowlegde, but I will throw out one idea. I am not familiar with the LX/AC system. However, on other Lexus products there are a couple of dampers, (flapers) that sit up against the cabin firewall and control the mixture and type of air (cold & hot) coming into the cabin based on the settings you program on the dash. I have seen members post about these dampers becoming stuck or loosing the power from the source that controls them. Unfortunately, I can't remember if the're electric or air powered. If they are not stuck the sevo's that move the dampers back and forth maybe bad.

It seems obvious that they had unhooked the negative battery line thus erasing all your electronics settings. And at the same time this problem happens. I would suggest pressing them further for an explanation.

Paul