2005 EB 4X2 A/C Air Conditioning blows room temp

[pohoda]

The air conditioning suddenly stopped blowing cold. It just blows room temperature air. It was working fine and then all of a sudden a few days ago it stopped. I have tried to put the A/C on auto climate control and also regular A/C with top vents on. The rear A/C also only blows room temp air. I looked at the compressor and it appears to be engaging and staying engaged. What troubleshooting steps can I take to determine the root cause? Thanks.

 

[locosol96]

There could be any number of things causing this. You could have a leak somewhere along the line. Do you have access to an AC test system with a leak detector (UV Dye)?

Also, the main return line could be rusted out. Not as common on the '05s as the '03s, but you never know.

 

[pohoda]

There could be any number of things causing this. You could have a leak somewhere along the line. Do you have access to an AC test system with a leak detector (UV Dye)?

Also, the main return line could be rusted out. Not as common on the '05s as the '03s, but you never know.

Thanks for the reply locosol96. If there was a leak wouldn't the clutch disengage due to low pressure fault? I still need to check to see if the clutch is truly engaging, but I need a second person to help me so I can watch it when the a/c button is pushed. I have a friend that has the a/c checking equipment so I will go by soon to check it out.

 

[joezek]

My thought is possibly the blend door. That's a common problem, the blend door controls the temperature. The motor's have very weak plastic gears and they snap off. Have you tried cycling max a/c, and doing it when the engine is ice cold before the heater core has a chance to heat up? If the a/c is getting cold you might get cool air from the vents for a minute or two. This will help troubleshooting a little bit.

Also, do you have electric climate control or the 3 knobs? Sometimes the cabin temp sensor goes bad and it thinks the cabin is already cold, and shuts the air off.

Not sure on yours but mine holds 54 ounces. That's around 3LB 6 ounces. You could be down to 1 LB and the compressor will still run, but won't be very cold.

Also... just had this problem on my friend's Mercedes- a/c was room temp air. I serviced the freon with the recycle machine, got the exact amount in. Still warm air. Then I saw the high side pressure going super high, like 400 psi. I realized he has an electric fan for the condenser and it wasn't running. I checked the fuses and the condenser fan fuse was blown. I replaced it, problem solved.

 

[joedmti]

Did u get it fixed?

The A/C in my truck just quit one day. Mechanic went nuts working on it til he found that there was an issue with the wiring. He played with something
behind the front passenger tire. Just turned the wheel so he could access the wire in the wheel well.
It was no big wiring/electrical troubleshooting deal.
Matter of fact, happened twice. First time. it took the guy some time to work his way to the wiring behind the right front wheel.
Second time, I was at a different mechanic, said my AC cut out, told him about the wire behind the tire thing, he went straight to it, and had me cool in 2 minutes

 

[pohoda]

In my case I had a leak at the compressor hose connection flange. Unfortunately the design is a bit flawed because there is just one bolt on the flange which really should have two. Eventually the flange no longer makes a good seal and the whole hose has to be replaced. We tried to just replace the o-ring but the flange had become warped and the whole hose, which is over $200, had to be replaced.

 

[jleroy68]

Hot A/C air

My thought is possibly the blend door. That's a common problem, the blend door controls the temperature. The motor's have very weak plastic gears and they snap off. Have you tried cycling max a/c, and doing it when the engine is ice cold before the heater core has a chance to heat up? If the a/c is getting cold you might get cool air from the vents for a minute or two. This will help troubleshooting a little bit.

Also, do you have electric climate control or the 3 knobs? Sometimes the cabin temp sensor goes bad and it thinks the cabin is already cold, and shuts the air off.

Not sure on yours but mine holds 54 ounces. That's around 3LB 6 ounces. You could be down to 1 LB and the compressor will still run, but won't be very cold.

Also... just had this problem on my friend's Mercedes- a/c was room temp air. I serviced the freon with the recycle machine, got the exact amount in. Still warm air. Then I saw the high side pressure going super high, like 400 psi. I realized he has an electric fan for the condenser and it wasn't running. I checked the fuses and the condenser fan fuse was blown. I replaced it, problem solved.

My 04 Expedition Eddie Bauer started blowing hot about a year ago, heard/felt a slight hesitation when I started it just before I noticed the hot air blowing. Turned out to be fuse number 11. Today while driving realized it was blowing hot again. All fuses good. Read your reply, went out and tried cycling max and back, now I'm getting cold air again. Thanks.