2006 A/C checks out fine, but still doesn't cool.

[erick_csf]

Hello everyone, I am new to the forum here so I apologize if i leave too much info out or if i ramble too much.

First off I have a 2006 expedition with an A/C which is not cooling all the way. I can feel cool air wanting to come out but overall the temp has been coming out from the vents around 75 degrees. (placed a thermometer in the vents)

I live in San Antonio Texas, so yes it has been about 85-95 degrees outside.

We put some gauges on it and it seemed to read fine. I believe the high was 170 and the low was steady right around 28-30.

The freon level seemed to be fine. Under the glove box the black plastic cover felt cold(condenser?). The compressor was running fine as well.

So not too sure why I am not getting the cold air out of my vents. Of course it does get cold in the early morning or late at night.

Here is a little extra stuff that is going on with the A/C unit that may or may not be of some relevance.

1.The master control on the dashboard only works on speeds 4 and 5. Neither the fan nor the A/C will turn on when I rotate the switch to 1-3 setting.

2. The overhead control will not turn on the A/C either. It has power to it as the lights on the panel light up when I switch on.

3. The middle row and third row vents do not blow any air.

4. The middle row console control does not turn on or seem to control the A/C either.

5. When I do switch the overhead A/C control switch on, the rear of the cabin starts to make a hissing and clicking sound. Very low and steady sound. When I went to the back and opened the rear hitch, I noticed the sound coming from the right panel by right around the third row seat control switches.

I have read something about blending doors and am not sure if this could be my issue as well.

I just need to make sure I get this A/C working ASAP since the hottest part of summer is yet to come and I have a 1 yr old, a 5 yr old and a 7 year old that need to ride in this vehicle. The air circulation just isn't good and it feels pretty dangerous to have my young ones in there sweating bullets even with windows down.

If anyone could shed some light on this situation I would greatly appreciate it.

Thanks Erick_CSF

 

[stamp11127]

What was the ambient temp when you took the readings?

The first reading you should take is the static pressure before running the system. This will give you a ballpark indication of the amount of refrigerant that is in the system. It is usually close to the ambient temp.

So if possible let us know what the static pressure is. If the a/c has been on, let it sit to equalize the pressure between the low and high side, 30 minutes will do.

 

[erick_csf]

Wow. Thanks for the quick response.

Honestly I do not remember what the static pressure was. I know my father in law had hooked everything up and we took the readings and everything seemed normal, but again I don't remember the static pressure.

I can try and hook it up again and see what we get.

 

[stamp11127]

That would be good. Once you have the static pressure then run the a/c system on max. The line coming out of the accumulator should be getting very cold, sweating if there is enough humidity there.

 

[thenaaks]

A high side pressure of 170 sounds a bit low for your ambient temps. Should be putting out cooler than 75 degrees though.
Get your pressures figured out, then you'll know if it's something else. Blend door, vacuum line, etc. Sounds like you have several other gremlins. Good luck!

 

[geoffdaddy]

Does it cool at all while the car is in motion and quit when stopped? Check your electric condenser fan to make sure it is operating.

 

[erick_csf]

It cools when its cooler temps outside. So if there are a bunch of rain clouds or in the mornings or at night. When the outside temp is around 70-80ish, the A/C throws pretty cool air if not cold air. It will do this whether its parked or of its in motion.

On a very hot day like 85-95 degrees outside. You can feel a little cool air wanting to come out of the vents, but its mostly warm muggy air that shoots through.

****
Sorry I have been working late everyday so I haven't been able to check the pressures yet. Hopefully I can get done today.

 

[erick_csf]

Okay got the gauges hooked up... Ambient temp outside is 92 degrees.

High pressure reading 112

Low pressure also reading 112

Not sure what my next step is.

 

[stamp11127]

Once you have the static reading then you read the low and high side pressures with engine running, ac on.
Has anything been done to the system in the past?

 

[erick_csf]

Turned on ac

Started at about 350 high

After about 5 minutes reading shows
170 high
And
25 low


Inside temp is blowing out 85 degrees from vents

 

[erick_csf]

Nothing been done to ac while I have had it. Only had for about a year.

 

[stamp11127]

Google "r134a pressure chart" and look at the pdf from mastercool for pressure readings.
Your initial static pressure is close to the ambient temp so it would indicate the system has enough charge in it.
The pressures should adjust to the operating pressures within a few seconds once the ac is running and stay there. Since yours is dropping over time that would indicate a problem with the compressor or expansion valve if it uses one on the front evaporator.
Either way the system needs to be recovered/refilled to establish a baseline and/or to swap parts.

 

[erick_csf]

Well I am not sure I can get to a service center to take out all the refrigerant right now.

Perhaps I can look into getting the rear vents to work. I am trying to pinpoint some of these issues.

So as of right now the rear vents do not blow any air from top or floor vents when either the overhead switch in the front or the bottom switch on the console are turned on. I have tried every speed from the top controls as well as pushed the button "of the little man sitting down" from top to bottom (which I assume is rear passenger console control). Once I do that, the back console control does not trigger any air flow out the vents either.

The vents just seem dead in any setting I try. There is power to both the top switch and rear console switch.

I am wondering if it is a blower issue. Maybe a fuse? I wonder, if I can get these rear vents to start blowing air, I could see if the air comes out cold or still warm like the front dashboard vents. If the air is cold, then perhaps it is the front blending door issue that is causing the warm air from the front vents? If its still warm air then there could be some other issue.

Either way since emptying my refrigerant is not an option right now, perhaps I can try and figure out how to get the rear vents to blow air. Any tips how to get air flowing through those rear vents?

 

[stamp11127]

Do you have a voltmeter or test light? How did you determine there is power to the controls for the fan motor?

 

[erick_csf]

Okay got a meter to the connection into the rear blower. It's the black/light blue and red/orange wire. I am getting 0 volts into it. Decided to check the relay next, but I can not find the location of the auxiliary relay 2 box. I've been googling online but can't find location.

 

[erick_csf]

Any help finding this location?

 

[stamp11127]

Right rear panel right under the leading edge of the window.

 

[erick_csf]

Thanks for your continued responses. Well we ended up finding the fuse location for blower under passenger glove box on right side panel.

Low and behold the 107 fuse was completely missing. (Along with a bunch of other fuses)

I took out the 106 fuse 30 amp and put it in the 107 slot. The blower worked nice and strong. Now I have air blowing out of 2nd and third row vents.

Unfortunately I can not tell if the air is cold or not because it's already night time here and cool (from a rainy day).

As you said I have a bunch of different issues here with my system. When I turn on rear blower I can hear the very distinct clicking. It's coming from the actuator that directs air from top vents to low vents. I disconnected the lead from it and the noise is stopped. I have air coming from roof vents..


Okay long story short my next step will be wait till it's nice and hot tomorrow and see what my pressures are again and if it cools in the back or if it stays warm.

Thanks again for all of your support. Hopefully I can get this ac working soon. My kids need it.

 

[Goats]

If your blower only works on high that means your blower resistor is bad. The other issue is that you are low on freon. I live in south Florida and I'm the same temp as you are. The pressure for the low side should be around 40-45 psi. In other words you need to add freon.

 

[Sidetrackedstu]

I need to replace both of those small actuators in the rear AC. Sounds like that might be your prob too. 1st controls the temp, 2nd controls floor or roof vents. They have tiny little plastic gears inside them that are designed to fail. No clue as to what they cost yet, just took mine apart and used the guts to manually adjust.