I found the Ambient Air Temp Sensor! 2008 ProStar...

[Waterloo]

(06-10-2019 )Daytripper Wrote:  2010 prostar daycab...should I have the outside display on my dashboard cluster? Nothing but odometer...I even clicked thru the rest of the functions and no ambient temp readings.

This may explain why my a/c is cold in the am but during the heat of the day blows lukewarm...been chasing this a/c problem for quite a while now(new thermistors, new high temp cut out sensor, 2 new actuators, new receiver dryer, new a/c compressor). There is supposed to be a third actuator on the engine side...not sure if I can access it without evacuating the system...
I am getting lukewarm air thru dash vents when blower fan is off, driving down the road.... oh and also after replacing the g#**@@* 1800.00 body controller (thanks international)

You need one of these, I think it will solve quite a few problems...https://amzn.to/2Iwx9jh

Here is the switch you will need to properly operate the valve... https://amzn.to/2KfZrlt

Install it in the heater core inlet line. I have one and love it! I have heat and cold air, no more opening the hood to turn that heater core valve!