I have an 06 laramie, yesterday running the air on high, runs strong for 10 minutes then just stops pumping cold air, any ideas what may have caused this? Checked freon, gonna try and check the pressure switch today.


Thanks in advance.........

John

 

My apologies to the mods, I suppose I should have put this here in the first place...

 

Are you watching the compressor spin ok?

or I would guess your blend door broke like all the rest of us.

 

No compressor spin at all, looks like maybe the pressure switch or the compressor itself......

 

If it runs for 10 min, sounds like the compressor is fine.

Whats the reading on the low side, typically 35 cool/idle to 45+ hot.

Hope you have a manifold gauge set? I'm willing to guess like you said the system gets hot, and builds to much pressure kicking off the high pressure switch.

on r134a remember high pressure side is 3x what the ambient temp is, so if its 90 degress out, high side should read 250-270.

Did you feel the suction and discharge line? suction should be cold/sweating, and discharge hot to touch.

Hopefully the system isn't freezing up either, that would mean to low freon, is there frost on the line?

 

refer to this link for reference charts/pics

https://www.dieseltruckresource.com/...n-t272323.html

 

O.K. guys, checked everything out, everything is working except it seems like the computer is not telling it to come on, checked with the local dealer, they want $106 to check it out and they may be able to flash fix it, but they also mentioned $800 for a new tipm?

 

Try adding a little gas. My 03 did the same thing and if I turned it off for 30 min it would work for jest about 15 min then blow hot air .

 

I got codes this morning, looks like p 0533 and p0532, maybe I can get lucky with just a re-flash....Telling me the ac sending unit voltage is too high and too low.

Thanks for the help all......