508GT SW 2014 - Climate control always blow air on windscreen

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sniglom
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508GT SW 2014 - Climate control always blow air on windscreen

Unread post by sniglom »

I have a 508GT SW from 2014.
It seems like the climate control always blows air on the windscreen, regardless of what settings I choose on the dials.

The two settings for the feet and vents towards the passengers seems to turn on and off as intended. This is annoying, since the automatic settings doesn't get enough heat to the feet or body, most of the air goes to the windscreen.

What could be the cause for this? Broken servos, cogs or flaps somewhere?

If it matters, I recently changed the heater matrix, if that could mess something up.
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GiveMeABreak
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Re: 508GT SW 2014 - Climate control always blow air on windscreen

Unread post by GiveMeABreak »

Hi

Normally air distribution settings and the air mixing settings for models with dual zone climate systems are managed by stepper motors for the left and right sides. If you had a particular problem with the air distribution not going to one side in particular or not going to the windscreen, vents, or lower areas, I would suggest that one of these motors is at fault or the the plastic gearing has shredded.

So you need to be specific by undertaking some tests.

I would first start by opening all the vent covers and then put the system on AUTO mode to get everything back to standard settings.
Then assuming you have dual zone climate control (separate controls for the front passenger and the driver) I would start on one side and increase the fan speed to maximum, then select the top / windscreen air flow setting. It should take a second or 2 to change direction to the top. The if successful, change only the direction to the middle / vent setting and again check that the air flow now diverts as required and ditto for the lowest setting.

Then put it back to AUTO and repeat all this on the opposite side. This is the only way without a diagnostic kit to check the air flow distribution motors are working.

As for the heater matrix, I would only suspect a problem if it was the actual TEMPERATURE that was playing up on the left or right sides - as in cold air only on one side, which would indicate a blockage or air lock within the cooling system. This can happen if you have drained and refilled the cooling system and not bled or degassed the system correctly which can cause air locks in the system.

As you haven't mentioned this, but only the air distribution, I can only assume it is one of the motors or attached spindles that has broken or some damage as a result to you changing the matrix.
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Marc
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sniglom
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Re: 508GT SW 2014 - Climate control always blow air on windscreen

Unread post by sniglom »

Hello,
First of all, thanks for your thoughtful and well written reply!

"If you had a particular problem with the air distribution not going to one side in particular"
I know for a fact that heat goes to the passenger side (that's why I switched the heater matrix).
But I haven't tested thoroughly whether the middle and bottom vent works as intended on the passenger side, only the driver side.

> I would first start by opening all the vent covers and then put the system on AUTO mode to get everything back to standard settings.
Auto always blows heat at the windscreen, if the fan is running.

"Then assuming you have dial zone climate control (separate controls for the front passenger and the driver)"
I do.

"I would start on one side and increase the fan speed to maximum, then select the top / windscreen air flow setting. It should take a second or 2 to change direction to the top."
I believe I only can change the fan speed for both sides, not individually.
Switching to the top vent doesn't do much, because auto already blows air to the top.
Ie, setting it to auto and high heat so the fan spins up, then pressing the top vent button, doesn't change much.

"The if successful, change only the direction to the middle / vent setting and again check that the air flow now diverts as required and ditto for the lowest setting."
Airflow diverts to middle or bottom (at least on the driver side). I have tried switching between the settings and I can feel the difference when the vents open and close for middle and bottom.
But it always blows at the windscreen too, even if I manually select only bottom and middle on both sides.

"I woould suggest that one of these motors is at fault or the the plastic gearing has shredded."
Where are these motors and gears located? Sounds like a good place to start looking.
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GiveMeABreak
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Re: 508GT SW 2014 - Climate control always blow air on windscreen

Unread post by GiveMeABreak »

Forget the heat side of things for the moment.

Putting it on AUTO is just to reset it to default settings as this adjusts the temp and airflow distribution based on set temp. Of course when you then manually set the distribution of the air flow (again, we're not interested in the heat at present, so just set the temp to 21 which is about normal), it should deflect the air to the desired location. I really just want to see if the air distribution on both sides is going where it is commanded (top, middle or bottom).

Accepted that the fan Air speed is for both sides - so put this on Max for the purposes of the tests. If the air flow output remains at the top level and does not obviously redirect the air to the middle or lower area then we have to assume either a faulty stepper motor, rods or a fault with the climate control unit.

On vehicles with 4 zone Air Conditioning there are plastic rods connected to the that operate the various flaps (Reduction Motor Rod Kit), which are available, so one assumes this may be a common problem over time.

The motors / rods are attached to the main heating assembly, so requires disassembly of trim to access.
Please Don't PM Me For Technical Help

Marc
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sniglom
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Re: 508GT SW 2014 - Climate control always blow air on windscreen

Unread post by sniglom »

I'm quite sure that it's the distribution that's broken.

I found these pictures in the forum. Do you know which of the motors and rods that are related to the windscreen?
I believe that rod F and G are attached below the heater matrix, which I replaced recently.
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