I have a 2004 GX470 and experienced the same blinking A/C light issue. I replaced the A/C Magnetic Clutch Relay with an aftermarket replacement from O'Riley Auto Parts and it worked like a charm. The cost was about $17.

 

This worked for me on my 03 GX but of course I went outside with the new part, opened up this thread and first tried the locations in the first and second pics in this thread. Third time was the charm. Above is the correct location on my 03. MG CLT.

PO had a cheap Made in China relay in that location definitely not OEM. Swapped in a Denso xxx28 I found on Amazon for less than $20 and AC light has not blinked since and AC stays on. Great fix.

 

I have this blinking "Check Air Conditioner" issue on my 2008 GX470. I tried to replace the A/C magnetic clutch relay and it did not help.

I tried the A/C diagnostic mode by turning on the ignition while pressing Auto and Circle at the same time, and the display just went to the regular Climate screen (with all buttons not working on the Nav screen) without showing any error codes. Pressing the Circle key again makes it go to the test mode when it tries all possible combinations of the fan speed and the air direction, with the blinking A/C button and not showing any codes either. What am I doing wrong?

 

Make sure you actually replaced the correct relay, as it appears that different years have it in different places. Refer to the owner's manual, or the lid on the fusebox.

How have the temperatures been? If you're low on refrigerant, the usual pattern is one side stays warmer than the other, but that's not a strict rule.

Chip H.

 

I am not a car expert but I am 100% sure I replaced the correct relay, as per the scheme on the lid. I actually tried the part from 2 different shops, just to make sure the replacement is not broken.

The temperature - if you mean when the AC is in a "non-AC" mode, I would say it blows the same warm air on both sides. I would not say it is low on refrigerant, because the issue started suddenly, rather than slowly increasing temperature of the air coming from the AC. Anyway, is there an easy way to check the refrigerant level?

The AC fan on the radiator starts when I turn on the AC, and stops almost immediately, and the "check AC" appears on the nav screen.

One thing I did not mention earlier - Just a couple of weeks before the AC blinking started, I had a mechanic change the timing belt (with a serpentine belt and whatever else is in the TB kit) and I just found that I was completely out of coolant, and generally the clips holding the engine cover were mostly missing. So I am skeptical about their overall quality of work , but would like to know what could go wrong at the time of the TB replacement, so I can argue when they potentially talk some bull-crap trying to convince me the AC issue is not their fault.

I am also wondering why the AC diagnostic mode is not showing any errors, but I may be doing something wrong here, because I could not find any proper instructions how to use it if you have navigation - everybody always describes the no-nav models.

 

I think it's time you took it to a car A/C specialist and let them troubleshoot it. Hopefully the earlier mechanic didn't mess anything up too bad.

Chip H.

 

I did end up taking the car to the mechanic and they found that the ground wire on the A/C was loose or disconnected. They fixed that and also did change the relay, saying it was possibly damaged by that wire disconnection. I have got the old relay but so far was too lazy to verify if it is really broken. They could not officially confirm that it was the previous mechanic's mess that caused all this. Thanks for your responses.

 

I just wanted to say thank you. had similar problem - ac blinking. no codes.
ordered a generic module on ebay for 7usd. replacement 3min. all works.
how can anybody charge for this more then 100usd - even with original parts - is beyond my understanding.

 

My GX470 AC quit blowing cold with a flashing AC light. I replaced the compressor and magnetic clutch relay with an OEM part. Had the system charged full. I thought that dId the trick but after a few minutes of cold air, the AC light starting flashing again and no cold air again.

I don't know what could be causing this. Any help would be extremely appreciated.

 

Anyone have the location of the rear evaporater.? Would help to know before I start tarring into car consoles etc. thanks for any help.

 

Back right, in the cargo area behind the panel. It's in the white box on the right.
Note that removing the panel is tricky. See this thread:

https://www.clublexus.com/forums/gx-...subwoofer.html

Chip H.

 

Good afternoon and Happy Thanksgiving all,

I am trying to find a good condition used 2007+ GX470 here in the Dallas area. Found a couple of While ones that seem to have been very well taken care of - but both have AC issues. The one I looked at today (2007 model) has a pretty long history of attempted AC repairs on the Lexus Owners site (pulled history using VIN#). Below is the diagnosis and repair history at the Lexus Dealership here in Dallas. I am liking the car otherwise, if this AC repair would not be super expensive (>>1k) I would like to buy the vehicle. Currently has 177k and if offering for $10.5k. I am sure she will come down to $10k easily. I took a short test drive today and the engine is very responsive. She had the rear setup changed in the past year - changed to springs but also replaced with new shocks also.

Looking for advice from folks who have faced AC issues and can provide any advice on this.

At 128k miles passenger side was cooling okay but driver side was not blowing as much cold air. Found to be 1 lb low on freon and was recharged.

Then at 134k miles (3 months later) AC system was checked for leaks with UV detection light. Here are exact notes - Found rear evaporator and lines leaking, system looks corroded in the rear and may require additional repairs. Need to start with replacing rear ac evaporator assembly. ~ ~ ~ ~134007 rear ac evaporator and lines leaking. The only place there was any dye was in the rear evap. Case 750 replaced rear evaporator and the sub hose assembly coming off expansion valve, replaced all orings. Evac and recharged ac system.

Then 5 months later at 140k miles these are exact notes - Need diag time to locate leak. ~ ~ ~ ~140601 evac and recharge 100 complete evac and recharge of ac system. Found leak at the front evaporator core and the ac compressor is also starting to make a knocking noise. Client waiting on repairs for now.

Six months later at 146k miles here are the notes - Client states a/c not cooling, would like is recharged ~ ~ ~ ~146351 evac and recharge ac system 100 noted that last visit leak found from evap core. Recovered 0.24lbs r-134. Charged with 1.69lbs r-134.

10 months later at 158k miles - Client states: ck a/c not cooling properly-seems to only blow cold air at passenger side until the car runs for 15/20 minutes-see previous visit ~ ~ ~ ~158659 low on freon by .87 off pound. Perform evacuate and recharge at this time a/c is working at factory specification. (i recommend to remove a/c evaporator and expansion valve for inspection, a/c compressor is noisy.)

What should I do? If the expected repairs will be less than $1k I would like to buy this vehicle - of course will get it inspected first.

Please give your suggestions.

Regards
Sanjay Goel

 

[Edit]

Moved my reply to his other post. Mods please remove this and the one above as they're off-topic.

Chip H.

 

Thanks for this post, OP. Saved us big time in Tucson last weekend. Air felt "warm" it was hot outside. Read this post from my phone, had it changed out in 5 min. Air is perfect now.

Thanks again,

K

 

which is the rear evaporator? if there's a leak, is it possible it's from the rear evaporator? i dont want to pay the dealer a lot of money to rip my dash apart.