I have a Hummer H3 2007, 3.7L with A/C problem - the compressor kicks on and off all the time. the compressor works for 20 seconds and then disconnect and repeat this cycle. In hot weather it can't cool enough.
Any ideas what can be the cause?

 

Welcome to HF.

Have you checked the refrigerant pressure?

If you are low, the compressor will not continuously run so that it does not burn itself out.

You could have other problems, but do the easy stuff first.

 

Hey, thanks for the quick reply.
No I didn't check, how this part looks or what is it's part number?

 

If you do not know how to check the AC refrigerant PSI, either Google it and educate yourself, buy the pressure gauge and do it, or..........

take it to a reputable repair shop so they can check it.