A/C Problem 2002 F150 SuperCrew
#1
11-09-2007, 06:05 PM
A/C Problem 2002 F150 SuperCrew
Ok, I posted yesterday with the A/C problem in 2002 F150 SuperCrew. (A/C defaulting to the Defrost vents... etc.) Had it in to another shop that did a vacuum test with the smoke machine and found no leaks... other than that did virtually nothing to the truck except to tell me that it is possible that this year model might have an electric motor that controls the "Mode Door" (Not the "BLEND" door, as everyone agrees that is electric...) rather than the vacuum control that folks have suggested it might have. The guy at the shop said this was likely as it has the "semi-automatic A/C" versus the manual control that the earlier year models had/have. Can anyone shed any light on this, either verifying that this MIGHT or MIGHT NOT be the case, or just debunk this statement altogether? Any help is appreciated.
#2
11-09-2007, 09:57 PM
#3
11-09-2007, 10:15 PM
#4
11-09-2007, 10:18 PM
maybe check the hose going behind teh battery- see photo
https://www.ford-trucks.com/forums/6...hlight=no+heat
https://www.ford-trucks.com/forums/6...hlight=no+heat
#5
11-10-2007, 05:06 AM
I'll Check the hoses myself...
Thanks for the response, Steve. I'm not sure I have a lot of confidence in this guy, either. I would say it is entirely likely that he is full of crap. That said, however, he DID say that he ran a vacuum test with the smoke machine and could not find anything. Not sure really how thorough he was.... I will check all the vacuum lines myself as best I can visually, and thanks again for the help. I am also taking the vehicle to a Ford Dealer this morning to see what their diagnosis might be. It's weird though... with the A/C off, only using floor or defrost, the system will switch back and forth between floor or defrost, but will not switch back to the panel vents, so it seems that two out of the three are working properly, just not the panel.... doesn't this seem weird?
#6
11-10-2007, 07:45 AM
#7
11-10-2007, 07:59 AM
from the manual---one vacuum door for floor and another for defrost.. maybe one door is stuck, or the controller **** is bad... again, does it switch on and off when you push throttle?
OFF
When OFF is selected:
l The A/C inlet duct door is at full vacuum, closing off outside air and admitting only recirculated air.
l The panel/defrost door is in the no vacuum position, closing the passage to the instrument panel A/C registers.
l The floor/panel door is at full vacuum, closing the passages to the panel/defrost outlets.
l The blower motor and the A/C compressor are off.
PANEL/FLOOR
When PANEL/FLOOR is selected:
l The air inlet duct door is at no vacuum, blocking the recirculated air passage and admitting outside air.
l The panel/defrost door is at full vacuum, closing off airflow to the windshield defroster hose nozzle.
l The floor/panel door is in the partial vacuum position, allowing airflow to both the heater outlet floor duct and the instrument panel A/C registers. There is also some airflow to the A/C side window demisters.
l The A/C compressor will be enabled when PANEL/FLOOR is selected.
l The blower motor is on.
FLOOR
When FLOOR is selected:
l The air inlet duct door is in the no vacuum position, blocking recirculated air and admitting outside air.
l The floor/panel door is in the full vacuum position, directing all airflow to the heater outlet floor duct.
l The temperature can be adjusted to mix airflowing through and around the heater core to achieve the desired temperature level.
l The panel/defrost door is in the no vacuum position, blocking air circulation to the instrument panel A/C registers.
l The A/C compressor will be disabled when FLOOR is selected.
l The blower motor is on.
FLOOR/DEFROST
When FLOOR/DEFROST is selected:
l The air inlet duct door is in the no vacuum position blocking recirculated air and admitting outside air.
l The panel/defrost door is in the no vacuum position directing airflow to the windshield defroster hose nozzle.
l The floor/panel door is in the partial vacuum position, allowing airflow to both the windshield defroster hose nozzle and the heater outlet floor duct. There is also some airflow to the A/C side window demisters.
l The A/C compressor will be enabled when FLOOR/DEFROST is selected to dehumidify the air and reduce windshield fogging.
l The blower motor is on.
DEFROST
When DEFROST is selected:
l The air inlet door is in the no vacuum position, admitting outside air.
l Both the panel/defrost door and the floor/panel door are in the no vacuum position so that most of the incoming air is directed to the windshield defroster hose nozzle. There is also airflow to the A/C side window demisters.
l The temperature setting will determine the amount of air that is directed through the heater core and the amount that bypasses the heater core.
l The A/C compressor will be enabled when DEFROST is selected to dehumidify the air and reduce windshield fogging.
l The blower motor is on.
Manual A/C Electrical Components
OFF
When OFF is selected:
l The A/C inlet duct door is at full vacuum, closing off outside air and admitting only recirculated air.
l The panel/defrost door is in the no vacuum position, closing the passage to the instrument panel A/C registers.
l The floor/panel door is at full vacuum, closing the passages to the panel/defrost outlets.
l The blower motor and the A/C compressor are off.
PANEL/FLOOR
When PANEL/FLOOR is selected:
l The air inlet duct door is at no vacuum, blocking the recirculated air passage and admitting outside air.
l The panel/defrost door is at full vacuum, closing off airflow to the windshield defroster hose nozzle.
l The floor/panel door is in the partial vacuum position, allowing airflow to both the heater outlet floor duct and the instrument panel A/C registers. There is also some airflow to the A/C side window demisters.
l The A/C compressor will be enabled when PANEL/FLOOR is selected.
l The blower motor is on.
FLOOR
When FLOOR is selected:
l The air inlet duct door is in the no vacuum position, blocking recirculated air and admitting outside air.
l The floor/panel door is in the full vacuum position, directing all airflow to the heater outlet floor duct.
l The temperature can be adjusted to mix airflowing through and around the heater core to achieve the desired temperature level.
l The panel/defrost door is in the no vacuum position, blocking air circulation to the instrument panel A/C registers.
l The A/C compressor will be disabled when FLOOR is selected.
l The blower motor is on.
FLOOR/DEFROST
When FLOOR/DEFROST is selected:
l The air inlet duct door is in the no vacuum position blocking recirculated air and admitting outside air.
l The panel/defrost door is in the no vacuum position directing airflow to the windshield defroster hose nozzle.
l The floor/panel door is in the partial vacuum position, allowing airflow to both the windshield defroster hose nozzle and the heater outlet floor duct. There is also some airflow to the A/C side window demisters.
l The A/C compressor will be enabled when FLOOR/DEFROST is selected to dehumidify the air and reduce windshield fogging.
l The blower motor is on.
DEFROST
When DEFROST is selected:
l The air inlet door is in the no vacuum position, admitting outside air.
l Both the panel/defrost door and the floor/panel door are in the no vacuum position so that most of the incoming air is directed to the windshield defroster hose nozzle. There is also airflow to the A/C side window demisters.
l The temperature setting will determine the amount of air that is directed through the heater core and the amount that bypasses the heater core.
l The A/C compressor will be enabled when DEFROST is selected to dehumidify the air and reduce windshield fogging.
l The blower motor is on.
Manual A/C Electrical Components
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#8
11-10-2007, 07:43 PM
Now I'm confused...
First let me say thank you, Steve, for the wealth of information. Amazing, and thank you again.
After a trip to Ford Service this morning, and after what you have said I am even more confused. Service reps talked amongst themselves, consulted the parts dept. and finally came up with the answer that yes, it might in fact, have an electric motor that controls the blend door. Unfortunately, no one can seem to say conclusively one way or the other. They say they can't tell until they get in there and have a look. I skipped that, as just the diagnosis alone would have cost me $100.
Anyway, there is no control ****, it is all digitally selected. We swapped out the controller and the problem still exists, even with a different control head in the truck.
When the truck is cold, first thing in the morning, it will work normally for 15 minutes, then cuts off the panel vents, and will blow out everything else fine. It will blow out the defrost by itself. it will switch and blow fine from the floor, or it will do a combination of both, but just not the panel vents.
After the truck is shut off for a little while (but still warm) when restarted it will work fine, but this time for only about 5 minuted or less. Doesn't matter whether the temp selected is hot or cold, that part all seems to work fine as well.
The last thing, is that it makes no difference whatsoever what the throttle is doing... whether it is at idle or at high rpm, the same problems/symptoms still exist, with the very same pattern. Defrost and floor will work fine, either separately or in combination.
I am about ready to search this forum for the instructions on how to pull the Dash/Panels for myself, and just replace everything in there on General Principle. The Dealership is telling me that it is about a $1000+ job to pull the dash... I'd sure like to avoid that, but I am pulling my hair out here. You wouldn't think that the make-up of the components in the dash would be such a mystery..... but no two people at any of the shops that have looked at it have the same thing to say. You, Steve, are the only one who seems to know what the heck he is talking about and you have had more useful info than anyone I have seen here. Thank you again for the help and suggestions, any more that you might have with this new info from me about the pattern of operation here (or lack thereof) will be greatly appreciated.
After a trip to Ford Service this morning, and after what you have said I am even more confused. Service reps talked amongst themselves, consulted the parts dept. and finally came up with the answer that yes, it might in fact, have an electric motor that controls the blend door. Unfortunately, no one can seem to say conclusively one way or the other. They say they can't tell until they get in there and have a look. I skipped that, as just the diagnosis alone would have cost me $100.
Anyway, there is no control ****, it is all digitally selected. We swapped out the controller and the problem still exists, even with a different control head in the truck.
When the truck is cold, first thing in the morning, it will work normally for 15 minutes, then cuts off the panel vents, and will blow out everything else fine. It will blow out the defrost by itself. it will switch and blow fine from the floor, or it will do a combination of both, but just not the panel vents.
After the truck is shut off for a little while (but still warm) when restarted it will work fine, but this time for only about 5 minuted or less. Doesn't matter whether the temp selected is hot or cold, that part all seems to work fine as well.
The last thing, is that it makes no difference whatsoever what the throttle is doing... whether it is at idle or at high rpm, the same problems/symptoms still exist, with the very same pattern. Defrost and floor will work fine, either separately or in combination.
I am about ready to search this forum for the instructions on how to pull the Dash/Panels for myself, and just replace everything in there on General Principle. The Dealership is telling me that it is about a $1000+ job to pull the dash... I'd sure like to avoid that, but I am pulling my hair out here. You wouldn't think that the make-up of the components in the dash would be such a mystery..... but no two people at any of the shops that have looked at it have the same thing to say. You, Steve, are the only one who seems to know what the heck he is talking about and you have had more useful info than anyone I have seen here. Thank you again for the help and suggestions, any more that you might have with this new info from me about the pattern of operation here (or lack thereof) will be greatly appreciated.
#9
11-10-2007, 08:54 PM
again, im no expert. i dont know how the electric climate control is different than standard, but the standard has 1 electric motor to "mix" the hot and cold air to get the right temperature. it is variable from 0 to 100% on temp, thats why it must be electric... the selection on where the air goes is all vacuum cylinders that control doors in the duct. they are on- off, not variable, thats why they can be vacuum controlled. basically there are three cylinders. on lets air into the duct when things are "on" that must be working. the second opens to let air go to the floor, and closes to keep the air inside the duct for somenting else. the last door of cylinder is closed to put air to the defrost, and vacuum opens it to get to the panel vents. im guessing that is the vacuum cylinder that is bad. when it fails, you get defrost. if you set to "floor" the other door opens and the floor vent works.---- its alos possible it is a bad hose to the cylinder from the controller. since you did the controller, i gues we can assume the controller is not the problem.-------- somewhere at the top of the duct behind the radio area is a vacuum cylinder and hose the moves the air to the panel or to the defroster-- thats the place to look----------again, assuming the electronic controls are like the standard-- i thought the electronic had a version to adjust the temp different from the driver to passenger side?? is that all?
#10
11-10-2007, 09:06 PM
#11
11-12-2007, 10:30 AM
DC, from what I gather, your Screw has the EATC (Electronic Air Temperature Control) system like my KR. When you are talking about your problem do you have the system in automatic operation mode or in MAX AC?
When mine is in AUTO, it will alternate where the airflow is directed among the panel vents, the floor, and the defrost. This paticularly happens when driving for longer periods and the system is maintaining a set temperature level. From my 2002 CD manual on the EATC system operation. Good luck!
System Airflow Description — EATC
AUTO
When AUTO is selected:
The temperature control setting is manually set to the desired setting.
The air inlet door vacuum control motor is automatically controlled by the EATC module, based on the temperature setting.
The mode door vacuum control motors are automatically controlled by the EATC module, based on the temperature setting.
The A/C compressor is automatically controlled by the EATC module based on the temperature setting. The A/C compressor will not operate if the outside temperature is lower than approximately 6ºC (43ºF).
The blower motor is on. The blower motor speed is automatically controlled by the EATC module, based on the temperature setting, but can be manually overridden.
OFF
When OFF is selected:
The air inlet door is at full vacuum, closing off outside air from entering the passenger compartment.
The panel/floor door and panel/defrost door vacuum control motors are at no vacuum, closing off airflow to the defrost duct, side window demisters, floor duct and instrument panel A/C registers.
The A/C compressor will not operate.
The blower motor is off.
MAX A/C
When MAX A/C is selected:
The air inlet door vacuum control motor is at full vacuum, closing off outside air from entering the passenger compartment.
The panel/defrost door vacuum control motor is at full vacuum and the panel/floor door is at no vacuum, directing airflow to the instrument panel A/C registers. A small amount of airflow from the side window demisters will be present.
The A/C compressor will operate if the outside temperature is above approximately 6ºC (43ºF).
The blower motor is on.
PANEL
When PANEL is selected:
The air inlet door vacuum control motor is at no vacuum, admitting only outside air into the passenger compartment.
The panel/defrost door vacuum control motor is at full vacuum and the panel/floor door vacuum control motor is at no vacuum, directing airflow to the instrument panel A/C registers. A small amount of airflow from the side window demisters will be present.
The temperature can be adjusted to heat the air, but the air cannot be cooled below the outside air temperature.
The A/C compressor will not operate.
The blower motor is on.
PANEL/FLOOR
When PANEL/FLOOR is selected:
The air inlet door vacuum control motor is at no vacuum, admitting only outside air into the passenger compartment.
The panel/defrost door vacuum control motor is at full vacuum and the panel/floor door vacuum control motor is at partial vacuum, directing airflow to the floor duct and the instrument panel A/C registers. A small amount of airflow from the side window demisters will be present.
The temperature can be adjusted to heat or cool the air below the outside temperature.
The A/C compressor will operate if the outside temperature is above approximately 6ºC (43ºF).
The blower motor is on.
FLOOR
When FLOOR is selected:
The air inlet door vacuum control motor is at no vacuum, admitting only outside air into the passenger compartment.
The panel/floor door vacuum control motor is at full vacuum and the panel/defrost door vacuum control motor is at no vacuum, directing airflow to the floor duct. A small amount of airflow from the side window demisters will be present.
The temperature can be adjusted to heat the air, but air cannot be cooled below the outside air temperature.
The A/C compressor will not operate.
The blower motor is on.
FLOOR/DEFROST
When FLOOR/DEFROST is selected:
The air inlet door vacuum control motor is at no vacuum, admitting only outside air into the passenger compartment.
The panel/floor door vacuum control motor is at partial vacuum and the panel/defrost door vacuum control motor is at no vacuum, directing airflow to the floor duct, defrost duct, and side window demisters.
Temperature can be adjusted to heat or cool the air below the outside temperature.
The A/C compressor will operate if the outside temperature is above approximately 6ºC (43ºF).
The blower motor is on.
DEFROST
When DEFROST is selected:
The air inlet door vacuum control motor is at no vacuum, admitting only outside air into the passenger compartment.
The panel/floor door and the panel/defrost door vacuum control motors are at no vacuum, directing airflow to the defrost duct and side window demisters.
Temperature can be adjusted to heat or cool the air below the outside temperature.
The A/C compressor will operate if the outside temperature is above approximately 6ºC (43ºF).
The blower motor is on.
When mine is in AUTO, it will alternate where the airflow is directed among the panel vents, the floor, and the defrost. This paticularly happens when driving for longer periods and the system is maintaining a set temperature level. From my 2002 CD manual on the EATC system operation. Good luck!
System Airflow Description — EATC
AUTO
When AUTO is selected:
The temperature control setting is manually set to the desired setting.
The air inlet door vacuum control motor is automatically controlled by the EATC module, based on the temperature setting.
The mode door vacuum control motors are automatically controlled by the EATC module, based on the temperature setting.
The A/C compressor is automatically controlled by the EATC module based on the temperature setting. The A/C compressor will not operate if the outside temperature is lower than approximately 6ºC (43ºF).
The blower motor is on. The blower motor speed is automatically controlled by the EATC module, based on the temperature setting, but can be manually overridden.
OFF
When OFF is selected:
The air inlet door is at full vacuum, closing off outside air from entering the passenger compartment.
The panel/floor door and panel/defrost door vacuum control motors are at no vacuum, closing off airflow to the defrost duct, side window demisters, floor duct and instrument panel A/C registers.
The A/C compressor will not operate.
The blower motor is off.
MAX A/C
When MAX A/C is selected:
The air inlet door vacuum control motor is at full vacuum, closing off outside air from entering the passenger compartment.
The panel/defrost door vacuum control motor is at full vacuum and the panel/floor door is at no vacuum, directing airflow to the instrument panel A/C registers. A small amount of airflow from the side window demisters will be present.
The A/C compressor will operate if the outside temperature is above approximately 6ºC (43ºF).
The blower motor is on.
PANEL
When PANEL is selected:
The air inlet door vacuum control motor is at no vacuum, admitting only outside air into the passenger compartment.
The panel/defrost door vacuum control motor is at full vacuum and the panel/floor door vacuum control motor is at no vacuum, directing airflow to the instrument panel A/C registers. A small amount of airflow from the side window demisters will be present.
The temperature can be adjusted to heat the air, but the air cannot be cooled below the outside air temperature.
The A/C compressor will not operate.
The blower motor is on.
PANEL/FLOOR
When PANEL/FLOOR is selected:
The air inlet door vacuum control motor is at no vacuum, admitting only outside air into the passenger compartment.
The panel/defrost door vacuum control motor is at full vacuum and the panel/floor door vacuum control motor is at partial vacuum, directing airflow to the floor duct and the instrument panel A/C registers. A small amount of airflow from the side window demisters will be present.
The temperature can be adjusted to heat or cool the air below the outside temperature.
The A/C compressor will operate if the outside temperature is above approximately 6ºC (43ºF).
The blower motor is on.
FLOOR
When FLOOR is selected:
The air inlet door vacuum control motor is at no vacuum, admitting only outside air into the passenger compartment.
The panel/floor door vacuum control motor is at full vacuum and the panel/defrost door vacuum control motor is at no vacuum, directing airflow to the floor duct. A small amount of airflow from the side window demisters will be present.
The temperature can be adjusted to heat the air, but air cannot be cooled below the outside air temperature.
The A/C compressor will not operate.
The blower motor is on.
FLOOR/DEFROST
When FLOOR/DEFROST is selected:
The air inlet door vacuum control motor is at no vacuum, admitting only outside air into the passenger compartment.
The panel/floor door vacuum control motor is at partial vacuum and the panel/defrost door vacuum control motor is at no vacuum, directing airflow to the floor duct, defrost duct, and side window demisters.
Temperature can be adjusted to heat or cool the air below the outside temperature.
The A/C compressor will operate if the outside temperature is above approximately 6ºC (43ºF).
The blower motor is on.
DEFROST
When DEFROST is selected:
The air inlet door vacuum control motor is at no vacuum, admitting only outside air into the passenger compartment.
The panel/floor door and the panel/defrost door vacuum control motors are at no vacuum, directing airflow to the defrost duct and side window demisters.
Temperature can be adjusted to heat or cool the air below the outside temperature.
The A/C compressor will operate if the outside temperature is above approximately 6ºC (43ºF).
The blower motor is on.
#12
11-12-2007, 04:30 PM
KRMAN02: A/C Problem
Thanks for the info! I appreciate it. Steve was very helpful as well and sent similar info about the routing/function of the air system,.... BUT.... no one (including the dealership) seems to be able to verify positively whether or not the "Mode Door" is vacuum or electric. There seems to be some disagreement and debate about whether or not it is or isn't.
Here's what is happening in a nutshell: When truck is started cold, after exactly 15 minutes (every time!) the vents stop working. Still have control over whether the air goes to the floor or the defrost, but no vent action at all. It doesn't matter whether heat or A/C is selected. Thereafter, when started hot, the vents will work again, but only for exactly 5 minutes, every time.
These symptoms don't seem to lend themselves to either a vacuum issue or an electrical. It is a complete mystery to me. Dealership wants $1000+ to remove dash and panels, diagnos and fix problem. I don't wanna do that, but I really don't want to attack this job myself, either, especially without a prety darn good idea of what might be causing this problem. Any ideas? Thanks for the help...
Here's what is happening in a nutshell: When truck is started cold, after exactly 15 minutes (every time!) the vents stop working. Still have control over whether the air goes to the floor or the defrost, but no vent action at all. It doesn't matter whether heat or A/C is selected. Thereafter, when started hot, the vents will work again, but only for exactly 5 minutes, every time.
These symptoms don't seem to lend themselves to either a vacuum issue or an electrical. It is a complete mystery to me. Dealership wants $1000+ to remove dash and panels, diagnos and fix problem. I don't wanna do that, but I really don't want to attack this job myself, either, especially without a prety darn good idea of what might be causing this problem. Any ideas? Thanks for the help...
#13
11-12-2007, 04:41 PM
I am not sure if Steve's post was for the EATC or if it was for the regular heating and cooling system with *****. I have not timed my EATC to know when it begins switching to other vents while in auto mode.
What mode is displayed besides the set temperature or outside temperature when you experience this symptom? Auto, Max AC, Panel, Panel/Floor, Floor, Floor/Defrost, or Defrost?
What mode is displayed besides the set temperature or outside temperature when you experience this symptom? Auto, Max AC, Panel, Panel/Floor, Floor, Floor/Defrost, or Defrost?
#14
11-12-2007, 05:10 PM
#15
11-12-2007, 07:08 PM
MODE makes no difference
It seems to make no difference which mode the system is in. I have started the system in all of the various modes individually, and all have the same result in the end, with the exact same timing. It does not matter whether I am in Auto, Max A/C, Vent, Panel, Floor, or Panel/Floor... after the same amount of time the same thing happens.
After what you guys have said, I am starting to think that the problems DO, in fact, sound like a computer problem. I am assuming that there is no other controlling computer besides the one found in the control head?
Here's the reason I say this: In my original post I mentioned that a Ford Service Rep told me that this was a sign of a control head going bad. Well, the dealership that I bought the car from (NOT a Ford Dealership, unfortunately) told me they swapped out the head with a different module (same kind) and that it did the same thing. OK, so I'm a dumb*ss, but I never actually SAW them do this, and they put the original back in, saying that was not the problem. My dealer said that he would replace the EATC with a new one, but that even if that did not fix it, he would be done with his obligations to fix the A/C. Thinking (hoping) that it might be something simpler, I chose to hold off on doing that because I didn't want to let him off the hook so easily if that didn't work, but now I am thinking that if I have them install the new EATC head anyway, then at least I can rule that out and KNOW that it is brand new and NOT the problem. Even if I do have to eat any further repair expense....whatya think guys?
After what you guys have said, I am starting to think that the problems DO, in fact, sound like a computer problem. I am assuming that there is no other controlling computer besides the one found in the control head?
Here's the reason I say this: In my original post I mentioned that a Ford Service Rep told me that this was a sign of a control head going bad. Well, the dealership that I bought the car from (NOT a Ford Dealership, unfortunately) told me they swapped out the head with a different module (same kind) and that it did the same thing. OK, so I'm a dumb*ss, but I never actually SAW them do this, and they put the original back in, saying that was not the problem. My dealer said that he would replace the EATC with a new one, but that even if that did not fix it, he would be done with his obligations to fix the A/C. Thinking (hoping) that it might be something simpler, I chose to hold off on doing that because I didn't want to let him off the hook so easily if that didn't work, but now I am thinking that if I have them install the new EATC head anyway, then at least I can rule that out and KNOW that it is brand new and NOT the problem. Even if I do have to eat any further repair expense....whatya think guys?