AC Works, MAX AC is dead

[danbike]

Well, yesterday was a hot one in Chicago. The dash thermometer read 100 for the first time.

The AC works fine, but when I hit the MAX AC button, nothing added. Feels like the door that controls the air intake is not working. I have an extended warranty and the car is less than 1 year old, so I'm not worried.

Any ideas what is kaput??

That's a technical term for not working, if you don't understand language from the Fatherland.:(

[fastblackmerc]

Well, yesterday was a hot one in Chicago. The dash thermometer read 100 for the first time.

The AC works fine, but when I hit the MAX AC button, nothing added. Feels like the door that controls the air intake is not working. I have an extended warranty and the car is less than 1 year old, so I'm not worried.

Any ideas what is kaput??

That's a technical term for not working, if you don't understand language from the Fatherland.:(
Maybe the blower motor resistor or the A/C - heater control head?

[danbike]

In the max ac setting it's like you are getting regular ac. Blower works fine.

[jgc61sr2002]

Faulty relay or resistor.

[03SILVERSTREAK]

Faulty relay or resistor.


^^^What he said^^^

[MENINBLK]

Well, yesterday was a hot one in Chicago. The dash thermometer read 100 for the first time.

The AC works fine, but when I hit the MAX AC button, nothing added. Feels like the door that controls the air intake is not working. I have an extended warranty and the car is less than 1 year old, so I'm not worried.

Any ideas what is kaput??

That's a technical term for not working, if you don't understand language from the Fatherland.:(

Mine has worked the same way since day 1.
If you have a roof, here is how you can tell the difference.
If you don't have a roof, try doing this with the REAR WINDOWS opened slightly.
It won't work as well as a sunroof, but it may give you enough to notice the difference.

With the roof in the VENT position and the HVAC in the AUTOMATIC Position,
set your temp to 60F.
Turn the FAN to the LOWEST SETTING.

If it is working normally, you will feel a very big draft coming through the vents,
because the Sunroof VENT is drawing air from the cabin, and through the HVAC system.

Now switch it to MAX AC.
The amount of air flowing from the dash vents should minimize,
because MAX AIR
recirculates inside air and shuts the HVAC vent door for outside air draw.
This is going to limit the amount of air the sunroof vent will draw from inside the cabin.

If you do not notice a difference, then the door could be stuck or just needs adjustment.

Take your Marauder to your dealer and tell him what you've done.

[Marauderjack]

I think when it is HOT the "Auto Control" puts it in "Max" anyway and when you manually select "Max" it is already there ......sooooo no change?? :confused:

I'll check mine today and see what happens?? :cool:

Marauderjack :)

PS: Somebody PLEASE turn off the rain!!!!!!! :mad2: :bigcry: :censor: :fire: :cry:

[metroplex]

On my 00 Vic w/ the manual ATC (the EATC has a processor that can go bad on the earlier models. Plus it has a sensor package, etc... Even tho I'm an EE, I despise relying 100% on SS electronics), the MAX A/C is simply A/C with the air intake diverted.

In Max A/C, this mode is known as "RECIRC* w/ A/C in non-Ford nomenclature. It will recirculate the interior air and cool the interior air as it passes out into the vents.

In Normal A/C, the intake air comes from the cowl and gets cooled as it goes into the cabin.

When I see a dust storm ahead of me, or someone's crappy car is smoking, or the driver is :bandit: (typical SE MI manners - smoke w/ windows down so that everyone gets second hand downstream of your car) I switch to MAX A/C and get the fugoudadere. The air doesn't necessarily get cooled FASTER except it just increases efficiency of the cooling.

NOW the problem is, whatever sensor the A/C uses to prevent freezing of the condensor picks up that the intake air is not hot enough, it releases the A/C clutch so the compressor isn't running. Technically it does increase efficiency because you're taking in cold air to get cooled faster. Once it reaches a certain point, the A/C no longer kicks in because it's already "cool". Except ambient radiation from the sun and your car seats makes you feel hot/warm.

Does this make any sense? Probably not, but the EATC probably does a lot of this automatically.

[RoyLPita]

Go be a faulty max door actuator motor and/or control head. Take it in and keep us posted.

[djv5150]

I had a similar problem had it in the shop last Friday my ac only worked on high.stuck could not turn off this is what they replaced.
F8VZ-19E624-BC, EATC Speed Controller Kit with Harness, $108.38

[David Morton]

"Automatic" brings in outside air and "Max AC" recirculates the inside air. Max is always the most efficient because moisture laden outside air just has to have the evaporator remove the water before it can get down to removing the BTUs from the air, so on automatic the compressor has to run more to maintain the same temperature.

The easiest way to tell if it's working is to turn off the radio and listen to the sound of the blower get louder coming from under the passenger side of the dash when you switch to Max AC. It's the only downside to the setting for me. I keep mine at Max AC all the time and know it keeps the compressor off more so I get better gas mileage.

[Bowman9]

As David said ""Max AC" recirculates the inside air"
Make sure that nothing is blocking the inside vent under the passanger side of the dash.
I had this happen to me once in my mustang, it turned out to be a plastic bag blocking the vent.

[wchain]

PS: Somebody PLEASE turn off the rain!!!!!!! :mad2: :bigcry: :censor: :fire: :cry:


We'll take it down here


"Automatic" brings in outside air and "Max AC" recirculates the inside air. Max is always the most efficient because moisture laden outside air just has to have the evaporator remove the water before it can get down to removing the BTUs from the air, so on automatic the compressor has to run more to maintain the same temperature.

The easiest way to tell if it's working is to turn off the radio and listen to the sound of the blower get louder coming from under the passenger side of the dash when you switch to Max AC. It's the only downside to the setting for me. I keep mine at Max AC all the time and know it keeps the compressor off more so I get better gas mileage.

Are you sure? Because I know if I set my car to 60 and Hit auto, whenI press Max nothing changes, because the car is looking to achieve the lowest temp as quickly as possible.

When it gets cooled off in the car, I will turn it up to 68 or so and I can feel/smell the outside air coming in, and the fan speed adjusting accordingly.....my 96 Explorer Eddie Bauer did the same thing

[danbike]

It was a loose vacuum line on the actuator for the blend door. Took Libertyville LM about 1 hour to fix. Got the car back with NO RATTLES in the dash. Now that is what I call good service.:banana2:

[FlyinMerc]

Just got mine back from the shop, same syptoms as yours: A/C works fine but max settings made no change. Problem was a disconnected vacuum line. Technician reached under the dash and reconnected vacuum line to blend door actuator. No dashboard removal, took ten minutes. No charge. Unfortunately, it came that way from the factory, been driving around like that for 16 months. I only noticed because of odors entering the car when the max setting should have recirculated the air instead of letting in outside air. Have your vacuum lines checked out.
Well, yesterday was a hot one in Chicago. The dash thermometer read 100 for the first time.

The AC works fine, but when I hit the MAX AC button, nothing added. Feels like the door that controls the air intake is not working. I have an extended warranty and the car is less than 1 year old, so I'm not worried.

Any ideas what is kaput??

That's a technical term for not working, if you don't understand language from the Fatherland.:(