One day my air conditioner just stopped blowing cold air. It's an auto climate system. Here's what I've done so far:

Checked low side pressure, its right at 45psi
Compressor clutch engages fine
Secret menu code was 00. Also did calibration mode and that completed ok.
Cabin filter changed

Not sure what other troubleshooting steps I could take to narrow it down. I've read about the expansion valve failing but I'd like to try to narrow it down before I start tearing everything apart.

Any ideas or pointing me in a direction would be greatly appreciated.

 

I finally got my hands on some gauges. The pressure is approximately 45psi on both the low and high side. I am assuming it is the compressor at this point. I can't think of anything that would prevent the high system from getting pressurized other than the compressor, but I'm far from an expert.

Am I correct in assuming that if the compressor clutch is engaging (RPM drop, etc) then the pressure switch is ok?

Just want to be sure before I start dropping $ and labor on it.

Thanks!

 

Sounds right to me. I’m not a pro.

will you be doing the work yourself?

 

Yea. This will be the 2nd a/c system I'll be opening and fixing. All the parts arrive early next week so I'll be starting on Tuesday or Wednesday.

I know enough to do the labor, I just don't know how much I don't know about troubleshooting yet.

 

Just to update. I replaced the compressor (also flushed the system and replaced drier) and its blowing cold now. However, it doesn't seem to be blowing cold enough. It's an auto air conditioning system and it seems like the air temperature it's blowing isn't proper to what the setting is. When I have it set to 66 it blows almost ambient or slightly cool air (but I feel some warm air coming out at the feet sometimes). When I set it lower it does blow colder and the warmish air at the feet stops. When I put it on LO it blows cold air ok from everywhere.

 

Sounds like your blend / mix door

Did you run the calibration from the auto control panel?

 

Thanks for the suggestion.

I did run the calibration and it came back CC. Also, there were no errors being shown either.

 

The lever that actuates the mix door is behind the glove box. Not too hard to remove for visual inspection

See this tread for my experience with this:

https://www.northamericanmotoring.co...working-2.html

 

Solved the weird issue with the warm air. Turns out my OAT wires took a little damage when I was working on the compressor. Fixed the wires and everything is back to normal.

 

Good to hear you got it

OAT?

 

I'm also curious. OATwires?

 

Sorry, OAT = Outside Air Temperature. There's a probe at the front, left side of the grill that measures outside air temp. It uses that data to run the a/c in automatic mode.

 

Is there a diagnostic available for that OAT sensor? Like, something that can be run with a Foxwell unit? It's getting warmer around here, and I need to double-check if my daughter's AC is working after having replaced the AC compressor clutch/coil last Fall (it was already too cold by then to really feel a difference in the HVAC air with the AC on).

 

Not that I'm aware of. If you check the OAT display in your car it should be reasonable to what the actual temp is. I figured out mine had a problem when it was showing 120 degrees when it was actually 75 degrees outside. This is for the cars with the automatic a/c temperature control. The cars with the standard manual a/c won't have that OAT probe.