Technical Climate Control - airflow issue [broken actuator?]

[Andymacselespeed]

My AC system has had a moment, the passenger side is really cold at the vents (both sides set to LO, recirc, AC on), the drivers side is just ambient air, or only a touch below. I've tried the heater system reboot procedure, pressing the two buttons, getting the countdown, lots of flaps moving about etc. Still the problem persists. I can change the temperature to go from really hot, down to outside temperature air coming in, but it won't get AC cold on drivers side! Even from cold so no engine temp to warm the air up. The full range of temps works fine on passenger side, from HI all through LO, hot air, down to icy cold AC.

Any ideas?

Cheers

Andy

 

[Deckchair5]

That's the whole beauty of having climate control, you can have it freezing on one side of the car and hot on the other- unfortunately not always the way you had it planned. Obviously a distribution problem rather than an A/C problem- there's been a few threads on one sided climate control- have a search

 

[Andymacselespeed]

That's the whole beauty of having climate control, you can have it freezing on one side of the car and hot on the other- unfortunately not always the way you had it planned. Obviously a distribution problem rather than an A/C problem- there's been a few threads on one sided climate control- have a search

I give up, I have search my little heart out and I'm none the wiser.

The AC works, the passenger side is cold. The air distribution flaps work fine as I get air on the screen, the face, and the feet fine. The temp selection systems works as I get Cold through hot on both sides AC off, but I only get the proper chilly AC air on the passenger side.

I've removed and checked the pollen filter which was claen but all leafy. I've checked AC pressure using a home AC filler thingy.

Where should I be looking. searching for one sided AC, one sided heater, heater distribution etc. I'm just getting results refering to air to either top middle of bottom not working.

Is it possible that one side of the AC matrix is clogged up a bit? If so how does one go about clean the matrix without taking the dash to bits?

Ta

Andy

 

[Morty Mort]

I was posting in a thread about this some time ago. A guy from Portugal (I think) had found the problem. There are two Bosch modules, on on each side, with a main flap inside. They are at the lower mid of the dash.

I will try to find it.

 

[Andymacselespeed]

I've found the post about the Bosch control modules, but I don't think that's the problem. I have full temperature control from ambient to really hot, only thing is I can't get ac cold air on one side. I can get air to any and all vents, just not ac'ed air!

Any thoughts on that?

Anyone got a diagram of stilo heating and cooling system?

Might be useful!

 

[Morty Mort]

I've found the post about the Bosch control modules, but I don't think that's the problem. I have full temperature control from ambient to really hot, only thing is I can't get ac cold air on one side. I can get air to any and all vents, just not ac'ed air!

Any thoughts on that?

Mine was behaving almost like that. Right side was normal, but left side (driver's) was usually hot. The only way to get cold air was when setting the climate to "low". That made it a bit chiller, and ice cold on the right side.

So, I went on the MOT (independent garage that just is a controlling authority, and don't repair) and asked them to take a readout at the same time. They found a fault at the AC climate control. So they erased it and the whole thing has been perfect ever since.

Würth WOW was the diagnostics program.

 

[Deckchair5]

[FONT=&quot]https://www.fiatforum.com/stilo/233242-climate-control-problem.html[/FONT]

[FONT=&quot]https://www.fiatforum.com/stilo/232263-heater-ventilation-reset.html[/FONT]

[FONT=&quot]https://www.fiatforum.com/stilo/24992-climate-control-cold-air-only-drivers-side.html[/FONT]

Motors/ flaps stuck or control. You have to find out which one is your problem. Find the flap that isn't moving, see if its stuck, see if it's being told to move, see if motor works




defrost and vent dist actuators









recirculation valve


right divertor flap

 

[Andymacselespeed]

I've spent a fair while this morning taking my car to pieces. I have found and checked the operation of two motors that change the diurection of air flow. I removed the glovebox, the passenger side foot vent panel, the drivers side foot vent panel, the drivers side cowling below the steering whell, the stereo, the heater control panel and the airbag deactivation key switch. I founf 2 electric motors connected to a series of white gears. One, seems to control aiur folw up towards the windscreen vernts, and the other seems to control air flow to the face or foot vents, I also stripped the windscreen wipers off, the scuttle panel and the plasticware around there to find the recirculating air flow flaps. All of these work fine, no trapped cogs, no broken cogs nothing wrong. I did realise that the cogs on the passenger side, operate through a connection rod to the drivers side to move air around. All of these flaps and cogs move freely and I can hear the flaps shutting inside the casing. Problem remains the same. I can still get full AC cold air to hot air on passenger side, and I can still get ambient air to hot air on passenger side.

Any more ideas?

Anyone know how to access the drivers side temperature control flaps? I can't see anything that moves only when temperature settings are changed!

 

[Matty A]

I had the passenger side jammed on boiling hot recently and found that the lower of the three actuators (black Bosch motors) tucked in behind the ashtray had sheared the flimsy plastic drive shaft. The motor was driving but the motion wasnt being transfered to the air mixture flap. I had to buy a pack of four drive shafts from FIAT.
The plastic drive shaft has a travel stop which contacts against the actuator casing to give the min and max limits. During the climate control reset procedure the motor drives the shaft around until the travel stop hits the actuator casing, feedback from the actuator gives the voltage for the min and max position and is used to determine the required flap position to give the desired temperature.
I would unbolt the actuator and ensure a white plastic (hex shape) shaft is sticking out, this engages with the flap linkage.

 

[Andymacselespeed]

I like this idea!

How did you go about changing the driveshaft?


I suspect mine is jammed or something as I can get hot, medium or near ambient air, just not really cold AC cold air.

 

[Xen]

Re: (yet another) Climate Control Problem

I've spent the evening getting to the actuators for the ventilation system and trying to understand what does what. Finally found the problem- the two black motors in the picture determine which vents the air is directed to. And the plastic gears that they are mounted to have BOTH sheared.

Next question: are they available to buy seperately? had a look on eper but it just shows the entire thing as a whole.

 

[Matty A]

Re: (yet another) Climate Control Problem

I believe they are the same as the air mixture actuator drive shaft. Photo 361 shows a sheared shaft, Photo 392 shows an actuator with drive shaft clipped in. These drive shafts/dowels are available in packs of 4.

 

[Morty Mort]

Re: (yet another) Climate Control Problem

This threas could possibly explain a great deal to all Stilo owners as it seems to be a common fault...

 

[Matty A]

As I said its worth pulling the bosch actuator off and looking for the sheared drive shafts. Just three gold coloured cap screws to remove.

If sheared drive shafts evident continue below:
I cut the end stuck within the actuator out with a scapel and dug the broken bits free using a small flat blade screw driver. The new drive shaft clips into place within the actuator. Make note the splines on the white plastic drive shaft are keyed to fit a certain way, and the hex end is also keyed internally when fitting to the air distribution box linkage.

remember when refitting the actuators to re-calibrate the climate control by turning the ignition to acc then pressing and holding both mono and auto buttons on climate control module. Leave everything alone until the climate control comes up with the familar screen with temps.

 

[Morty Mort]

I'd really like an explanation (step by step) how to get to it.

Big thanks anyway.

 

[Xen]

Re: (yet another) Climate Control Problem

I believe they are the same as the air mixture actuator drive shaft. Photo 361 shows a sheared shaft, Photo 392 shows an actuator with drive shaft clipped in. These drive shafts/dowels are available in packs of 4.

Thanks for that, I'll have a look to confirm that. And yes, the two motors look just like photo 361.

 

[Xen]

Re: (yet another) Climate Control Problem

Well, I've been having a look and you're right... the center of the plastic gear is removable, so it is possible to just replace the sheared shaft part. Thought it would be worth mentioning the plastic gears are also an orderable part for anyone else with this problem.

Matty A: Do you have a part number for them?
I had a look on ePer and I think i have the number, but just want to confirm because the diagram isn't very clear. If its '13' (which is simply described as 'lever') then its part 46723463. Its not number '12' since that part includes the motors.

 

[Xen]

I'd really like an explanation (step by step) how to get to it.

Big thanks anyway.

I'm taking photos as I go, so once i've done it, I might write up a guide

BTW, 46723463 is the right part number, but ePer lists it as single and not as a 4pk like 'Matty A' got Will try to get to the bottom of it

 

[Matty A]

Sorry i didnt get back, I am away from the computer most of the time on the weekend. The little ones keep me busy! The part number is correct and I had to order four as they were not in stock at my FIAT dealer . Though it will be worth hanging on to them as a suspect the others will shear also in time. Those actuators have electric motors driving a worm-if the flap gets jammed the worm will transmit quite a torque.
If you have the chance to write up a guide then that would be excellent. Could FIAT forum set up a wiki like the ford wiki?

 

[Morty Mort]

Fantastic. I've been watching these gears move and travel myself many times, but have never had any idea where to start - or how to get to them. I thought FIAT started with the climate control unit then built the car around it, finishing off with the nasty aerial and forgetting about the ugly impotent backbox.