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Climate Control Heater Issue

OP
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Cypress
Thread Starter #61
I think the Ford reps posted something about having to be away from the forum for a bit, but I agree, shitty timing.

siberiankiss - that sucks :(. Hopefully the next part helps, or at least gets them on the right track.
I'm really starting to think it's a software issue. Or at least it was with my car... since my heat doesn't work at all now they must have broken something in the "fixing" process.
 


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Toronto
#62
I'm really starting to think it's a software issue.
I've not owned a car that doesn't have vaccuum or direct mechanical operation of the blend doors and baffles in the HVAC system before, but the system in the FIST takes much longer to switch between the different vents. It is obviously controlled by a module using motors to operate the blend doors and baffles, with the buttons on the console providing the input.

The control module doesn't seem to be very consistent in its operation. Usually with Auto mode turned off and none of the HVAC buttons activated, it blows air out of the footwell and windshield vents. But sometimes if you press the dash vent button to turn those vents on then press it again to turn it back off, it won't turn the dash vent off. This doesn't happen every time, but there definitely is some inconsistency with the programming on the module. I expect the fix from Ford to be a replacement or reprogramming of whatever module controls HVAC.
 


DaveG99

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#63
Its almost like the temp controls don't work in the hot range. Its either full blast heat or nothing. 82 degrees is cold when it should be hot. This should not be an issue on a new car. Its not like heating is a new technology.
 


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Noneya
#64
I'm really starting to think it's a software issue. Or at least it was with my car... since my heat doesn't work at all now they must have broken something in the "fixing" process.
Yup, I agree. I believe there is computer involvement in the system and it isn't working right and needs some sort of update. Considering this is an auto system it has to read the temperature and adjust things accordingly so there is definitely computer involvement, I just don't know if that's through its own system/module or tied to the ECU. I think this computer is also involved in the manual temperature selection process as well because the selection of temperature is digital and the dial spins in either direction endlessly so there obviously isn't a mechanical link back there to determine how far the blend door should move.

I'm not going to bet money on it, but I really wouldn't be surprised if it ends up being a flash update type of fix in the end. Or I could be completely wrong, but there are only so many parts to the system and from the various people impacted by this I think most of those have been replaced and some of those people have probably had them all replaced so there isn't much else left to turn to.
 


OP
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Thread Starter #65
Yup, I agree. I believe there is computer involvement in the system and it isn't working right and needs some sort of update. Considering this is an auto system it has to read the temperature and adjust things accordingly so there is definitely computer involvement, I just don't know if that's through its own system/module or tied to the ECU. I think this computer is also involved in the manual temperature selection process as well because the selection of temperature is digital and the dial spins in either direction endlessly so there obviously isn't a mechanical link back there to determine how far the blend door should move.

I'm not going to bet money on it, but I really wouldn't be surprised if it ends up being a flash update type of fix in the end. Or I could be completely wrong, but there are only so many parts to the system and from the various people impacted by this I think most of those have been replaced and some of those people have probably had them all replaced so there isn't much else left to turn to.
I then I'll just end up with a bunch of broken plastic bits.
 


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Noneya
#66
I then I'll just end up with a bunch of broken plastic bits.
Yeah, dealers techs aren't kind to interior plastic when doing warranty work a lot of the time. That said, if they tear up your interior I would raise absolute hell until every piece that they scratched, that rattles, that doesn't line up right, etc, is fully replaced.
 


OP
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Thread Starter #67
I got a call from the dealer yesterday afternoon saying they had fixed the car. I was skeptical, but shockingly everything was working when I got in the car! I went inside to talk to my service rep, and find out exactly what part had fixed the car. The last part Ford had recommended they replace was the heater control valve. My dealer finally gave up on the Ford engineers and came up with their own idea to replace the control (I think this is the actual control panel with the knobs and everything), but that didn't do the trick.

The part that the dealer claims finally worked is the evaporator and housing. I don't know if there's some electronics in there that affect the climate control or what. They told me that they have basically replaced every part in the system at this point, so who knows if it was some combination of parts... All I know is I drove all the way to work in the cold this morning, and it worked just like I would expect it to!!!!
 


jayrod1980

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#68
I got a call from the dealer yesterday afternoon saying they had fixed the car. I was skeptical, but shockingly everything was working when I got in the car! I went inside to talk to my service rep, and find out exactly what part had fixed the car. The last part Ford had recommended they replace was the heater control valve. My dealer finally gave up on the Ford engineers and came up with their own idea to replace the control (I think this is the actual control panel with the knobs and everything), but that didn't do the trick.

The part that the dealer claims finally worked is the evaporator and housing. I don't know if there's some electronics in there that affect the climate control or what. They told me that they have basically replaced every part in the system at this point, so who knows if it was some combination of parts... All I know is I drove all the way to work in the cold this morning, and it worked just like I would expect it to!!!!
Please try this test when you get a chance. Drive the car with the system on auto at a mild temp... Like 75 degrees. Verify the blower and all that aren't going full blast and the car is relatively close to desired temperature. Then go to a gas station and let the car sit for 5 mins while you gas up. Then start up and see if the car (still set to auto) doesn't blow cold air from then on at any setting of auto other than high. As another option, you can roll into a parking lot and stop, go into reverse, etc and see if it doesn't go super cold again.

Personally, once I've triggered the AC from hell in one of this situations mentioned above, the car will blow cold and hard on auto no matter if I drive 100 miles in a cold climate condition. It will never adjust or blow warmer until I turn the car off for at least a half hour.
 


OP
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Thread Starter #69
Please try this test when you get a chance. Drive the car with the system on auto at a mild temp... Like 75 degrees. Verify the blower and all that aren't going full blast and the car is relatively close to desired temperature. Then go to a gas station and let the car sit for 5 mins while you gas up. Then start up and see if the car (still set to auto) doesn't blow cold air from then on at any setting of auto other than high. As another option, you can roll into a parking lot and stop, go into reverse, etc and see if it doesn't go super cold again.

Personally, once I've triggered the AC from hell in one of this situations mentioned above, the car will blow cold and hard on auto no matter if I drive 100 miles in a cold climate condition. It will never adjust or blow warmer until I turn the car off for at least a half hour.
I'll try this sometime in the next couple of days and let you know.
 


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#70
I got a call from the dealer yesterday afternoon saying they had fixed the car. ...... The part that the dealer claims finally worked is the evaporator and housing. .....and it worked just like I would expect it to!!!!
The dealer doesn't know because they aren't smart enough. When they pulled the evap/housing they had to disconnect the wiring, including the chassis grounds that are critical when working with the 5 VDC max signal values. All of you having the weird problems should do yourselves a favor and remove/clean the paint off/install tightly all the electrical grounds.
 


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#71
Please try this test when you get a chance. Drive the car with the system on auto at a mild temp... Like 75 degrees. Verify the blower and all that aren't going full blast and the car is relatively close to desired temperature. Then go to a gas station and let the car sit for 5 mins while you gas up. Then start up and see if the car (still set to auto) doesn't blow cold air from then on at any setting of auto other than high. As another option, you can roll into a parking lot and stop, go into reverse, etc and see if it doesn't go super cold again.

Personally, once I've triggered the AC from hell in one of this situations mentioned above, the car will blow cold and hard on auto no matter if I drive 100 miles in a cold climate condition. It will never adjust or blow warmer until I turn the car off for at least a half hour.
I noticed on my car that it starts to blow cold air at full blast when you open and close one of the doors. That seems to be what is triggering the HVAC system to malfunction in Auto mode.

I know its been asked before, but can anyone post a diagram or a list of all the grounds with locations so we can have them as a reference?
 


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#72
There are grounds all around the car but the ones you should check are behind the battery, above each front kick panel, one near the main connector just above and forward of the left kick panel, and one just forward of the heater/AC box.
 


jayrod1980

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#73
Honestly, unless they changed the gauge of the grounding wires,or location, why would the 2016 be the only year affected by this issue? Is there significant electrical load increase with the sync3 system that would cause the grounding to be suddenly inadequate for the climate control system?
 


OP
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Thread Starter #74
Honestly, unless they changed the gauge of the grounding wires,or location, why would the 2016 be the only year affected by this issue? Is there significant electrical load increase with the sync3 system that would cause the grounding to be suddenly inadequate for the climate control system?
Exactly what I was thinking.
 


DaveG99

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#75
Mine randomly worked last night. So weird. Most of the time it doesnt work.
 


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#76
I'll just say that the paint process is the problem, not the wire or the ground locations. I'll stop trying to help now.
 


jayrod1980

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#79
I'll just say that the paint process is the problem, not the wire or the ground locations. I'll stop trying to help now.
I'm not putting down your answer, I would just like to understand the difference. Didn't they spray or dip the earlier year cars? Since this is a 2016 issue, what has changed with the paint process?

I already planned on filing all of the grounding points on the car, but some areas are tight, and other than near the battery, where are they?
 


OP
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Cypress
Thread Starter #80
Please try this test when you get a chance. Drive the car with the system on auto at a mild temp... Like 75 degrees. Verify the blower and all that aren't going full blast and the car is relatively close to desired temperature. Then go to a gas station and let the car sit for 5 mins while you gas up. Then start up and see if the car (still set to auto) doesn't blow cold air from then on at any setting of auto other than high. As another option, you can roll into a parking lot and stop, go into reverse, etc and see if it doesn't go super cold again.

Personally, once I've triggered the AC from hell in one of this situations mentioned above, the car will blow cold and hard on auto no matter if I drive 100 miles in a cold climate condition. It will never adjust or blow warmer until I turn the car off for at least a half hour.
I drove for about 30 minutes this morning, stopped for gas, and had the climate on auto the entire time. Still worked perfectly.
 




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