Just bought my girlfriend an 03 gx470 with 201,xxx miles. Absolutley love the truck. Today we got in the car, and started it, while in the parking lot. The A/C was not ice cold, felt as though it was low on freeon, however, once we started driving, it reached normal temperature and got ice cold. We drove to my shop and I checked the pressures, they read 29psi and 135 psi after a 45 minute drive. I topped it off to 39 psi and 190 psi. Since outside temp was 92F and engine was bay was hot. No change, the condenser fan did not turn on. I hooked up a power probe and supplied the fan with 13.1 V, the fan kicked on. Checked the voltage from the harness and the voltage read 0.0, the compressor and everything else function normally. I checked the 20amp fuse, it was fine, I swapped the relay out with a good one, no change. I cannot figure out why the condensor fan is not coming on, however there is a grey two wire connector that is not connected to anything that has a 13.1V current. I am at a loss and any ideas would be greatly appreacieated. Lmk what you think.

That loose plug is “standard”....confused many owners here...might have something to do with trailering options....has nothing to do with your AC issues

It's rare for me to notice the condenser fan come on. Since the fan comes on when you supply power, it's good. And since you made sure the refrigerant levels were correct (like many modern cars, the GX is sensitive to having the right amount in the system) it's good.
I think you're seeing normal behavior.

No one knows what that extra connector is for. My theory was that it was for headlight washers, but if it's a constant 12v with the key on that's obviously not true.

Chip H.

Your AC is under-charged, or you have serious compressor and expansion valve issue. I suspect the 1st.
see https://rechargeac.com/how-to/ac-system-pressure-chart

The AC fan does not always run, which is normal.
What relay did you swap?
How did you check voltage on the harness? Most things on modern vehicles use current sinks to turn stuff on (nFET, npn, etc). From a connector pin to chassis gnd you should find voltage.

I would vacuum that AC and then add back the correct dose, then go from there. If the new 134a does not have oil in it then I would add 1oz of PAG46.

is the ac control set to let fresh air in?

You would likely get warmer AC when driving, OP seemed to suggest the opposite.
Could also be the flapper on that control doesn't close (open) 100% between settings. I believe this is what's going on with my AC, because sometimes the AC feels real cold, and other times not as cold (same ambients, etc). This leads me to believe some flappers are not working correctly.

What I'm saying is if the control is set to let fresh air in that is your problemand you WILL GET the problem you describe. It needs to be set to recycle air. In other words air from outside closed.

I know what you meant.

Why would fresh air setting be the problem?

Those AC pressure readings suggest a charge issue.

Because as you drive you will get varying results based on your speed (ram air effect) and the micro-climate you're driving through (tree-lined road vs. industrial area)

Chip H.

Yes, but OP didn't say cooler or warmer while driving, just said it got colder later on, etc.

It needs a AC vac and refill w/ some oil.

Imagine this: when you have that button set to let fresh air in, what temperature is the air you are letting in?
If it's 80 out you may get some cooling, if it's 108 outside you are not going to get very cool inside...lots of hot air mixing in your interior. It's like driving with the windows open and the ac on. Close that fresh air button. This is easy. I've had three of these cars, btw.

The fresh air setting does nothing but warm the AC air temps. OP said things got colder as they started driving, it eventually got ice cold. I don't think fresh air setting has anything to do with this. Vac it, dose it, add some oil as needed.