hzhao

When you say “non-responsive”, do you mean the system is completely shut down? Or it is running, just won’t be able to to change any settings, such as temp, air flow, etc. If it is completely down, for example, on your center screen, all the soft buttons are grayed out, then you may want to check the fuses first. If the A/C appeared working, such as display the correct temp setting, air flow, just won’t be able to change anything, then you may need a system reset. You can try to reset the system by disconnect the negative battery terminal for 10 minutes. This will clean all the system memory, then restart the car again. If all fails, being as 2018 model, I would assume that it is still under warranty, just take to dealer and have tech check it out, it could be a malfunctioned control unit.

dhan980

Well I see the temperature that was previously set but the buttons are non responsive as in nothing happens when I try to increase or decrease the temperature. I dont think the system is completely shut down but nothing happens when I click either the hard physical buttons or the virtual buttons on the GPS screen under climate.

hzhao

You can try the reset to see if that helps.

dhan980

Thanks for your response. If I may ask you a trivial question, can you also let me know how do you disconnect the negative terminal. I mean, would it require any specific tool to disconnect the terminal?

hzhao

You will need a socket ranch or adjustable ranch to release one nut from the battery terminal. But based on your question, I would seriously consider to take the GX to dealership as under warranty repair.

Acrad

If it become responsive after power cycle you can also run a diagnostic against the HVAC system

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

Acrad

Lexus Air Conditioning Systems Diagnosis Quick Training Guide

bambam2

2010 GX with the three zone system. Front driver and passenger vents blow strong heat and AC but the rear vents blow very weak. Do I have a blower motor going out? Is there a rear blower motor?

hzhao

There is a separate A/C unit for the rear. It is located passenger side behind 2nd row seat (if I remember it correctly). The temperature sensor is also located in that area.

CTML

I'm interested in a 2014 GX at a local Lexus dealer - when digging through the service history I saw 'EVAC Recharge' and 'Vents have odor' on three separate occasions since 2017. It sounds like a chronic issue with the A/C so wondering if the car is still worth pursuing / what the potential issue is.

My main concern is that they can recharge the A/C today and it blows ice cold, but a few hundred miles down the road the A/C fails again. I've searched the forums and A/C issues typically arise in 1st gen and much older cars.

Any thoughts on how I should address this with the dealer?

Lavrishevo

iTrader: (1)

Odors are usually caused by debris collecting in the condenser which causes mold or mildew to build up. Toyota actually makes a product that you pump up into this area and then you let it drain after it cleans it out I think it's a foaming style product. Usually more of an issue in areas of high humidity.

CTML

Got it, that makes sense - the car is in NY so presumably the mold / mildew build up is not humidity related and maybe the cause of a leak.

These are the service notes from 5/2020 and 1,000 miles ago which scared me:
DESCRIPTION:PERFORMED EVAC AND RECHARGE OF SYSTEM/ ~|~CUSTOMER STATES TO CHECK A/C SYSTEM, NOT BLOWING OUT COLD AIR, CHECK AND REPORT ~|~ ~|~54907 100 EVACUATE AND RECHARGE A/C SYSTEM SEE ON VISIBLE LEAKS MY NEED EXTENSIVE A/C WORK IF SYSTEM STARTS BLOWING WARM AGAIN

ASE

Clearly has a slow leak ... on the high pressure side (operating at 250+ PSI) where the hoses go thru the firewall into the evaporator coil that is in the heater box under the dashboard ... so finding the leak and resolving the recurring problem requires a fair amount of dash disassembly that probably does not have the "book time" to where the dealer is making any money on the job ... so they recharge the system and send the car on it's way knowing that it will work for a period of time before the freon completely depletes (based on severity of the leak, which in your case sounds slow ... so the leak is minor, which means it would be that much harder to find the location). I assume the major smell is probably for the duration of the freon leaking (when the AC is working), but does linger for some period after the AC stops working because of the oil added to the freon that has probably superficially coated an area under the dash surrounding the leak. The leak is probably at a hose fitting ... going into or exiting the evaporator coil ... or could be a leaking evaporator coil.

ASE

The condenser is in the engine compartment by the radiator. The evaporator is inside the vehicle under the dash. The problem is the system losing its freon charge ... not mold or mildew buildup on the condenser. Mold or mildew on the evaporator may be an issue which would smell musty, but that would be a secondary unpleasant problem that has nothing to do with the AC system losing its freon charge.

CTML

I think that's exactly right - they've recharged it every year for the previous owner to kick the can down the road.

I will call in tomorrow to confirm what work they've done to resolve the A/C - I guess for them to do a proper job and truly resolve the issue they will have to take out the dash and investigate the evaporator which I feel is highly unlikely what they will actually do...