AC NOT WORKING

[earnies2]

2009 prostar compressor not powering on. Can someone tell me how to diagnose
I have 85 lbs freon compressor off I jump compressor low side goes to 45 its 50 degrees outside....I cycled the system no go...ware should I look? I have a multimeter and test light

[Lonestar10]

i beleive rawze has a youtube video or 2 about common issues with prostar AC some pressure sensors i beleive on the side of the box mounted to firewall.

[Waterloo]

(03-15-2019 )earnies2 Wrote:  2009 prostar compressor not powering on. Can someone tell me how to diagnose
I have 85 lbs freon compressor off I jump compressor low side goes to 45 its 50 degrees outside....I cycled the system no go...ware should I look? I have a multimeter and test light

Check the high pressure switch wire, mine has broken a couple of time. Start at the switch, it should be up at the top of the radiator on the passenger side at the condenser line. You will have to pull back the split loom and have a look.

[earnies2]

Ware do the 3 wires go and should I have voltage or ground on any pins?

[earnies2]

How do you test the thermisters?

[earnies2]

3d grade was tough..... I looked everywhere for the AC videos I never thought to look on you tube.. well I found them now I can test the thermisters....I didn't see a test procedure for the high pressure switch...

[earnies2]

On another note I looked in my truck and I remember listening to the ac videos last year and did the reset switch and bought a receiver dryer,expansion valve,and a set of thermosters so I have all the possible parts except a high pressure switch after I test the thermisters I will post back

[earnies2]

All set I found the videos and metered the thermisters one was shorted changed them both now I need to charge the system thanks for all who helped this site is great