Having AC problems (2017 CX-5 GT)

[LoinCloth747]

AC blows cold when compressor is running, only really noticeable when 90+ degrees is the compressor runs for about 15 seconds blowing cold then shuts off for about 30-45 seconds give or take on both which blows cabin temp air very warm. This then causes the cabin to cool down very slowly if at all. I’ve charged the AC before maybe not necessary but I did. System has correct pressure. Auto care place said same thing and didn’t notice anything until he drove it home in the heat. His guy recommended a compressor relay which I have ordered. Any ideas?

 

[edmaz]

If it was dropping out, I'd expect there to be clicking from the relay, trying to reestablish the circuit. Not saying it can't be a bad relay, just expressing some doubt about it. If a replacement relay doesn't resolve the problem, then I recommend checking for power and ground to the compressor, either by backprobing the connector, or by using a wire piercing adapter.

 

[LoinCloth747]

If there was a bad hot side or ground wouldn’t it not be able to operate at all or for extended periods of time? It cycles the compressor frequently when I believe it should keep the compressor on.

 

[wlong01]

If the relay is ok move on to the compressor clutch.

 

[TheMAN]

evaporator probably frozen... check if refrigerant is too low
but usually it's an issue with the thermo switch in the evaporator or sticky expansion valve... pretty common on mazdas within the past 15 years, especially in high humidity conditions

if your car is under warranty, have the dealer look at it... some mazdas have TSBs regarding frozen evaporators too

 

[edmaz]

If there was a bad hot side or ground wouldn’t it not be able to operate at all or for extended periods of time? It cycles the compressor frequently when I believe it should keep the compressor on.

I like testing, and this is an easy test to confirm the compressor is being powered (or not) during the times when the compressor stops working. Others may choose to do other diagnosis first, but this is the way I'd start if it were mine.

 

[dunhillmc]

leaking/weak belt tensioner?