Recently bought a 2012. Just wanted to check that the A/C system doesn't have some deal where it only comes on above some particular outside temperature. If that's not the case, I guess I have some work to do in the spring. Does anyone have an A/C troubleshooting guide for these cars?

 

So, I'm not that familiar with these cars yet. Is there a pressure switch that precludes the compressor from running if the R134a pressure is low?

I'm familiar with early Miatas, and there's a low pressure switch that can be jumpered to make the compressor run to allow you to charge the system.

If there is such a switch, can it be jumpered in a similar fashion, and where is it located?

 

I would book it in with a Qualified A/C tech to test & diagnose your vehicle correctly.

 

Thanks for your idea.

 

I don't understand what you are really asking... The AC is based on your controls not your controls not outside temps.
NOW, if you are asking if it might not cool the car off when it gets hot that's a different thing....
For me.... when I bought mine. I was blowing ok but I know I would be using the car for traveling ALOT. so I just replaces everything because it's so cheap.
for $ 225-ish I changed the compressor condenser w/dryer attached and the expansion valve( located under the dash)
keep in mind.. mechanic labor are about $90 per hour. just to diagnose it it's already half the cost of DIY
Current ebay prices
compressor like $90
condenser - $96
exp valve - $15
Freon - I think 35-40 at walmart.
2 years later and I haven't a single issue with it.

On a side note I didn't vacuum the system. The amount of time the lines are exposed to the environment is minimal. Just leave the the plugs in until the last second
If you have lines hanging cover them until you connect them back up;

 

I'm assuming what you're saying here is really "The AC is based on your controls not outside temps."

I'm fine with that, if that's the case; I just need to do some more figuring out. AC is not working. Compressor does not engage when the A/C button is pressed on the dash. I have so far been able to confirm that the A/C clutch operates when 12V is applied direcly to the connector. Next up is to confirm operation of the A/C relay, and check all A/C related fuses, but the car is currently under 6" of snow so that'll have to wait.

It's not a comfort issue until summer, but it is a potential safety issue during winter for defogging purposes.

 

It it were me.... first order of business is to see if you have enough Freon in the system.
You can go to the auto parts store and get a BS gauge to check that. Or you can buy one attached to a can of freon then just check it and return the can.