C9 air compressor low pressure switch

[Bob Disney]

C9 air compressor low pressure switch
I have gotten a couple warning lights where my air compressor did not kick in in time.
Trying to figure out for sure what my pressure regulator looks like and how to replace it.
2005C9

[Bryan Beamon]

Bob, you are probably looking for your air governor located close to your air dryer. Try amazon to locate several different governors as an example of what they look like. The governor  regulates the high and low pressure cut off psi and can be manually adjusted. Suggest calling Cat with your engine # to get the correct replacement.

[Frank Bergamo]

Bob,

this might help you. https://www.napaonline.com/en/p/TWDBENOR275491X?cid=paidsearch_shopping_dcoe_google&campaign=GSC-Towing&campaign_id=8911645606&adgroup_id=106416389246&adtype=pla&gclid=Cj0KCQiA09eQBhCxARIsAAYRiylUxoxJRn7Mg9vvvHqpCCWctQHJM9eIj68Q0y7uxY6kNOr1wlJ0-BUaAhOkEALw_wcB&gclsrc=aw.ds&   Good luck.

[Bob Disney]

I was in a national forest going to go boondocking when our air issue started
Driving down the road the low pressure alarm went off
It was 30 miles just to get cell signal and then not enough to access internet
Ended up putting about 250 miles on toad trying to address this problem
Anyway I replaced the governor but still had a persistent problem.
Then working on the process of elimination I replaced the air dryer as it appeared to have never been serviced. I had been acting kinda weird as it would spit a little spit every 2 seconds or just allow a consistent volume of low pressure air, so I removed the spitter, cleaned it up and replaced it. No luck
Long story short I had received a bad governor as the first replacement
I replaced the governor a second time and it  did the trick 
I think I may carry a spare governor as a precaution as the are under $50 and quite small
If you decide to carry a spare the smart move would to carry extra fittings and hose as the originals had a few issues with removal.
Also on our coach the governor is not mounted on the air compressor, it is remotely mounted on the cross member holding the frame together just to the right of the engine, maybe a foot inside the engine bay opening. You have to look over the cross member and look for air lines.
If you have the right parts and a few tools its about a hour to replace it.