What does "AC" button actually do on my 2002 Escalade

[mattluttrell]

Hello,
My 2002 Escalade (160K miles) recently lost all AC. I took it to a mechanic and he noticed the belt had slipped. He replaced belt tensioner, belt, schrader valve and charged the system. It worked great.

5 days later the air isn't very cold at all but I believe it is something different. I would like to problem solve it myself before I take it in. I think it might be an actuator associated with the AC button.

Here is what I know:
1. Rear blows moderately cold air with "AC" switched on and rear set to cold.
2. Front air responds to temperature knob change. On a hot day it will only blow extremely hot air or moderately hot air in front.
3. Front responds to change in "recirculation" button change. I can fold down glove box and observe that flap moving.
4. Line going out of Accumulator is very cold and dripping condensation.
5. Compressor cycles as expected.

I believe there may be something associated with the "AC" switch which might not be working correctly. I think there may be an actuator that needs to be replaced since my compressor, condensor and accumulator appear to be operating correctly.

Could you please tell me what actually happens when I press the "AC" button? Is there something else I should be checking?

 

[YukonXL04]

The AC button signals the system to turn on AC. I would start by checking your freon level.

 

[SteveCZ28]

like mentioned above. a/c button triggers a/c to turn on. mainly engages clutch on compressor

but what youre describing sounds more like the blend door actuator is messed up( the one for temp, not vent position) the system still sounds charged to me being as youre hearing the compressor cycle, and the fact you have cold rear air.

 

[mattluttrell]

The AC button signals the system to turn on AC. I would start by checking your freon level.

The system is charged. There is no question of that.

---------- Post added at 12:13 PM ---------- Previous post was at 12:11 PM ----------

like mentioned above. a/c button triggers a/c to turn on. mainly engages clutch on compressor

but what youre describing sounds more like the blend door actuator is messed up( the one for temp, not vent position) the system still sounds charged to me being as youre hearing the compressor cycle, and the fact you have cold rear air.

This sounds like a feasible scenario. So you're saying I should drop the cover underneath the dash and pull the actuator in the middle just above the carpet? I could manually move that door as it might not be moving all the way towards cold?

 

[SteveCZ28]

yes. you should be able to do that.

by chance did you disconnect the battery at all recently? it might just require a relearn. which can be found on this site also.
basically disconnect battery for like 2 minutes. hook batt back up. turn key to on, but not run. let sit for i think something like 5 minutes, dont touch any settings on climate control at all. then shut key off for 10 seconds then good to go. thats what i remember atleast. but id still look it up

 

[mattluttrell]

I took this actuator off. I can manually shift it from luke warm to damned hot.



The compressor is working. The lines I'm pointing to are very cold.



What should I check next?

 

[ezdaar]

Ac button is the "All Clear, Punch it! GOGOGO!" button! Duh

 

[mattluttrell]

So when I manually move the blend door pictured above I can get 74F in the front and 50F coming out of my vents while it is 86F outside. What would cause a dramatic difference between front and back?

 

[FreshLikeOprah]

Your orfice tube may need to be changed. It goes in between the two lines that connect by a big nut. In between the high and low side connections. But your system will need to be recovered, vacuumed and I'd change the drier/accumulater as well.

 

[El Capitan]

Common issues with our truck a/c include valve on low side (which the mech said he replaced) the high side coupler, low side pressure sensor which is on the canister and orifice tube. those are all under $30 a piece at your local napa the only problem is you need an a/c machine to do any of it. i would start with those first, starting with the low side pressure sensor.