Hi all, we have 2012 vw routan that is not producing cool air at idle which I believe is due to the cooling fan not operating correctly at engine op temp. the cooling fan will start when the ac high side pressure reaches 275psi but it will run very slow. the high side pressure will continue to fall until about 175 then the fan would turn off and the high side would climb and repeat this at idle speed. coolant stayed at OP temp no overheat issues, the low side was about 39 and down to 33 when the high side was falling. I believe the temps that day were 75 and at idle discharge air was about 65, on the highway my discharge air was down to 44 and the humidity was high at about 70%, the ac clutch stayed engaged throughout. what should can i check?