2010 Expedition A/C Not Working and Knocking

[GreenTitan05]

Girlfriend's mom has a 2010 Expy that has a few problems with the A/C.

1) After its been sitting awhile and we crank it there's a knocking sound from behind the radio that comes in intervals for the first couple of minutes till it warms up. I think I found the answer to this in another thread:
SOME 2003-2004 EXPEDITION/NAVIGATOR VEHICLES MAY EXHIBIT A MOMENTARY GRUNT/POP FROM THE A/C SYSTEM WHEN THE COMPRESSOR IS ENGAGED AFTER THE VEHICLE IS PARKED FOR A WHILE, BEFORE THE ENGINE COMPARTMENT HAS WARMED UP. THIS CONDITION IS DUE TO REFRIGERANT BEING PUMPED OUT OF THE COMPRESSOR. WHILE MANY VEHICLES HAVE PCM STRATEGIES THAT ADDRESS THIS BY REPEATEDLY CYCLING THE COMPRESSOR ON START-UP, THIS MAY NOT COMPLETELY ELIMINATE THE NOISE. THIS IS A NORMAL CHARACTERISTIC AND REPLACING A/C COMPONENTS WILL NOT ADDRESS THIS CONDITION, SO DO NOT ATTEMPT REPAIR. TO MINIMIZE THE NOISE, TURN THE A/C SYSTEM TO VENT BEFORE EXITING THE VEHICLE, AND IN MILD AMBIENT TEMPERATURES (50-75F/10-24C) WAIT A FEW MINUTES BEFORE TURNING ON THE A/C OR DEFROST.

That was posted in 2005 so I'm hoping it still applies today which is unfortunate that Ford hasn't fixed this in 5 years. But that's the only thing I could find about it.

2) The rear roof a/c doesn't work. The front a/c blows fine but when you have 8 people packed in there in the summer, the 4 vents in the front just don't cut it. I haven't found much about this, people mention blend door and actuator being faulty and I'm not sure what any of those do. Can anyone give me the basic overview of the a/c system Ford uses? I have found that some people's heat will blow in the rear just not a/c. I haven't looked to see if her's does this because we don't use the heat in July in SC.

Anyone have any advice/info/explanations for this? Thanks guys

 

[bedrck46]

Go to ford etis and enter the vin number it will give you a readout of what all was on the expy when built

 

[stamp11127]

Are you mechanically inclined and able to do basic repair work or are you tool challenged?
The members here will taylor the responses accordingly.

 

[GreenTitan05]

I can do it myself, I have an 05 F150 I do a lot of work on so I should be able to given some guidance.

Bedrck: Why do I need the readout?

I've been doing some more research and for #1 I think its either the blend door, or blend door motor that's acting up. For #2 it could be the rear blower since (if its not blowing any air) or the rear expansion valve (if its only blowing hot air). I didn't get a chance to crank it yesterday to tell if it did blow any air but I did check all the fuses related to the A/C and they are all working fine.

 

[bedrck46]

only to let you know what equipment was originally installed it will also let you know if rear air was installed.

Based on your comment "I have found that some people's heat will blow in the rear just not a/c." It seemed that you were unsure if it had rear air.

If that is the case then look up the information on ford etis If you do indeed know for sure that you have rear air Then I am sorry for trying to add some confusion into the matter

 

[bedrck46]

Do you use any type of manuals for guidance?

 

[GreenTitan05]

My guidance is manly information I find on these sites or other places and the how-to-installs are from youtube or friends. That does make sense bedrck, I know it is suppose to be blowing air in the rear, its the full size expy with 3rd row, got bells and whistles for the little kids like dvd player and stuff etc. What I was trying to say was some people that have this problem can blow heat through the rear vents (meaning its most likely the rear expansion valve) and others can't blow any air at all (probably the rear blower). I was saying I haven't tested if it blows heat yet because its July in SC and its hot haha

 

[bedrck46]

try and see if it blows heat just before you park it for the evening at least you will see if it does and it won't have ant effect on anyone. I don't have the manuals for the 2010 but you may want to check all the controls to make sure the are in the proper positions
Will be sending you a PM for your information

 

[GreenTitan05]

Thanks for the PM I'll be sure to get one, got my birthday coming in a few weeks. And all the controls are fine, I'm just trying to find what it the most likely part that's being faulty. I would feel bad if I told them to buy this part, doesn't work, then buy this one, doesn't work, etc. and I keep wasting their money.

 

[bedrck46]

find out if the blower is working if it isn't the check your owners manual to see what fuse/fuses are for the rear unit

 

[GreenTitan05]

Yesterday I checked any fuse that dealt with A/C and they were all fine, where is the rear blower located and how to I tell if it is working?

 

[bedrck46]

the rear blower is located with the rear a/c heater unit it should be on the right side around the rear wheel not sure on the 2010

there are also some relays involved in the circuit again check your owners manual for theses relays

 

[Copper93]

Have you check the pressures? Some of these front and rear A/C systems can be picky when they are low on pressure.

 

[stamp11127]

Blower motor circuits are usually separate from the compressor circuit.

 

[GreenTitan05]

I haven't checked the relays yet but I was messing with the air last night, the front ac blows perfectly fine and a lot of pressure when on full. The rear blows no air at all so I'm thinking its most likely the motor that went bad. She did say that the rear air stopped around the same time the ticking of the blend door started. Could the two be somehow related? Is there a relay or something linking the two?

 

[GreenTitan05]

Update: Sadly I haven't done much more to solve the problems other than reading. I believe the clicking front A/C is from the common blend door motor acting up, the one directly behind the radio. The other problem with the rear air is most likely the motor. I'm going to push the radio and confirm its the blend door clicking and if I can find out how to get to the rear motor test that as well.

 

[stamp11127]

The front and rear blower motors both have a resistor pack that varies the speed of the blower. I would check to make sure that the pack is getting power before tossing any parts at it. They are usually mounted by the blower motors. One thing to look for is a melted plug, which is normal on these.