I've been in this truck just under 3 weeks. The a/c blows ice cold air WHEN IT DECIDES TO. That means it'll go from working absolutely perfect to not working whatsoever.

I've checked it and it's not freezing up. The shop took the system apart and flushed it out completely, plus recharged it, 2 days ago. Same thing. Apparantly they've been having issues with this A/C since they bought the truck last year. The owner said (2 days ago) that if it was still acting stupid, they'd be sending it to Volvo to find out what's going on.

Myself, I think it's a sensor somewhere inside. The truck has a true climate control system, with sunlight, humidity and temperature settings. My company doesn't have the software to connect to the body-control computer (only the ECM), so they can't diagnose anything inside the cab.

The weird thing is that it only stops working while you're driving. You can sit for 16hours with it blowing ice-cold air, but drive 2hrs down the road, and it dies.

When I parked @ 3:30 today, the A/C wasn't working. I shut the truck down for a little over an hour while I had dinner. Started the truck back up and let it run for an hour or so, no A/C. Shut it back down for 1/2 hours or so, started it up and ran for 15-20 minutes and now I'm freezing in here.

There's no huge tell-tale puddles of water under the truck from where it would've been thawing out.

Weird, right?

Mine is a Pete 379 and it was doing about the same thing. Seemed like there was a short and when I was moving it would cut out randomly.. sometimes not even starting back up for hours. I finally took it to peterbilt after it cut out in 110 degree heat in Houston and they did something inside/behind the glove box.. haven't had any problems since. I'm willing to bet its an electrical issue moreso than the system itself.

My thoughts as well. I just hope the boss does what he said and sends it to Volvo.

They *finally* figured it out. I was under a heavy load, going past the terminal, when the A/C decided to cut out. Went in and let the mechanic know. He came out, smacked the A/C clutch and it took right off. So, the truck has a new compressor on it now and it'll just about run you out because it's so cold.