We've been having a heat wave and today my AC didn't really cool very effectively. I hadn't really noticed an issue before this except it sometimes takes up to 10 minutes for the air to get really cold. Are these symptoms indicative of it needing to be charged or is something else going on?

 

Sounds like it needs recharging.

 

Does the outside temp look rational when you hit the EXT button?

 

There is a climate control front control panel bite test for codes that may somehow show low freon ( code 23 )

See you tube video and instructions on page 110

T703 BOOK (jagrepair.com)

Codes

14-10 (jagrepair.com)

There is a cabin temp sensor as the small square vent below the steering collum that gets clogged with lint and gives no code , only clean with air and a brush on the back inside side

 

Yes, that's reading accurately. It was about 90F/32C yesterday.

 

Aside from the obvious freon recharge , if the radiator fans do not kick into high mode to extract the energy out of the freon , that energy still in the freon comes back around to the cabin as poor performance ( high freon demand / load )

This is from the 4 wire freon pressure switch

To test the radiator fans in high mode , remove the 3 wire connector on the engine coolant temp switch on the lower aft left on the radiator

Jumper with a paper clip one white wire to the black , low fans mode

Remove jumper and jumper the other white wire to the same black , high fans mode

This is a low current section of the fans circuit so no arcing hazard

This will not test the 4 wire high pressure freon switch though , just simulates it's command , but does the fans high low fans relay control module

 

I'll give this a try. As it turns out the AC was fine yesterday on a long trip but the outside air temp was about 10F cooler outside. I did check the ac charge and it was fine. I gave it a couple of squirts so its higher in the good band.
When it was an issue at the higher outside temp in Auto the recirc mode stayed on with the blower at high speed but no colder air. I was thinking maybe the compressor clutch wasn't engaging.

 

With too much freon the compressor will disengage by the 4 wire freon pressure switch as it works as a high and too high switch

With cabin fans in high the output will not be colder but the volume of air moved will be higher and the cooling " amount " is a function of higher airflow and exit vent temp , the exit temp is designed to not go below 35 F so the evaporator will not freeze up