Technical Climate Control [faulty fan?]

[Deckchair5]

Manual air con
With manual aircon there is a bank of 3 resistors -shown here as O30- which provide the 3 speeds and speed 4 -the fastest- is straight through with no resistance.

The fan speed is controlled completely differently with climate control than it is with manual air con. All reference to resistor banks you have to forget when talking of climate control systems as they aren't relevant to you


With climate control the fan N85 has an integral electronic speed control unit controlled by a signal voltage supplied by the climate control ecu M70 from pin 11 to the fan pin 2 . A feedback voltage is supplied from the fan pin 1 back to the cc ecu at pin 8

But the basic supply and earth is the same. Supply comes in on red wire to fan on pin 4 and earth (black wire) is from fan pin 3 to earth point C16 That would be a first point of investigation -especially as you say it tends to go wrong in wet conditions. A loss of earth here woud mean the fan wouldn't have a circuit


C16 could be here but bear in mind it may be the mirror image as this is a lh drive picture

So, back to basics, if you can get to the fan connector, I'd check for 12v power on the red wire and a good earth on the black wire. Clean up the earth point C16


If there is a basic 12v power supply problem to the fan then I'd check this area, Fuse 8 and relay T8 in the engine bay



If it is a problem with the power control circuit board in the fan then look for problem areas on the circuit board - darkened areas or poor solder joints and you may be able to repair it. It gets wet in there with the air con and circuit boards and wetness don't go together well

 

[750nig]

The correct fan for a Climate Control model is just over £200, compared to £85 for a std heater fan.
With this incentive I have managed to get the fan apart and can get at the pcb. Will post pics later of seperated fan & pcb.
Can't see anything untoward on the pcb so many thanks Mr Deckchair for these circuit diags and tips. Will have a look see next weekend.

 

[750nig]

Pics as promised above. As you can see the fan does come apart but I have broken a couple of the 'legs' that hold it together, three left so should be ok. Mayber there is a less destructive way, but I clearly don't know it.

 

[daniel handley]

Re: 2004 fiat stilo abarth heater not blowing

hi just wonderd if any one could help i have a fiat stilo abarth and the heater has stopped blowing? it lets warm air through the vents but wen i turn the heater on to blow it duznt do anything? could any one help?
thanx dan

 

[Argonought]

Re: 2004 fiat stilo abarth heater not blowing

hi just wonderd if any one could help i have a fiat stilo abarth and the heater has stopped blowing? it lets warm air through the vents but wen i turn the heater on to blow it duznt do anything? could any one help?
thanx dan

Dan, you've pretty much answered your own question by posting in the exact thread that provides the answer (well done )

Not sure much more can be said really unless you have a specific question?

Welcome to the Forum BTW.

 

[daniel handley]

new to all this not realy sure what to do basicly on my fiat stilo abarth the heater duznt work ? thanx dan

 

[grundleweed]

i have same problem with my 02 abarth the RH centre fan was blowing hot even with the temp set to 16c someone had a look said it was the motor flaps and manually adjusted it so it was blowing cold rather than full heat.. although now it wont blow at all it was intermittent but now fully not working i get the odd 2 sec burst now n then

so im guessing its the fan motor
although someone at a fiat garage did they there were a few different motors behind the dash??

how much are these motors to replace? if i got one from another scrapped abarth would it work or does the part number have to be 100% match?

from what i read i take it i get to it from the drivers footwell. (cant you access it from passenger side at all asthe pedals wont be in the way?)

 

[john55]

Spoke to the dealer yesterday. If your fan is going slow, or not at all, New fan + wiring adapter for early cars with Climate control. £211 inc VAT.

If your fan is intermittently working and then not, it is more than likely a poor solder joint or connector.

 

[grundleweed]

mine was working intermitertly.. (usually stopping the engine and restarting fixed it) but its now more n more not working to the point where it doesnt work at all now.. ive just had the odd 3 sec blast of air.

the other question is if its not blowing out the fans is it ok leaving the fan speed on or shall i turn the air system off / lower the fan to slowest speed?

 

[Frantic fiat fanatic]

Hi. How did you get on with the motor repairs? Hope I haven't missed a thread.

The fan motor in my Stilo Abarth Selespeed (Nov 93) stopped working suddenly, although it did come on a couple of times by itself! To get it out I had to strip out the brake controls, accelerator pedal and steering gear, great fun. The motor was in a pretty dirty state and contained some leaves and signs of dried condensation/damp etc.

To separate the motor parts I found it possible to lift the fan on one side by gently levering up the fan, at the bottom between the top cover and the fan after removing the three screws, with a large bladed screwdriver. This action released two of the internal retaining legs.

I wedged between the fan and the cover with a thin strip of wood to retain the gap made and released the remaining two legs with a medium flat bladed screwdriver through the bottom of the fan blades. No damage, but mind the pcb!

The pcb is pretty dirty, covered with carbon and traces of copper from the brushes and commutator as well as general dust. Could have shorted out something or just increased resistance.

Now I have to release the commutator housing lugs to clean the comm, and then restake them, generally clean up before reassembling and testing out etc. Brushes seem ok, about one third worn over nearly six years and 36000 miles.

Of course, it might not work after all the effort, but at least I can clean all the connectors before final testing out!

Would love to know how you finally ended up with this one.
I've put some pictures in my photo gallery for viewing.
Best regards
Mike.

 

[Artful53]

For the last few days my 2003 1.9JTD with climate control has been intermittent but today the fan has stopped working completely even though the display shows the bar graph speeds varying. Reading through this thread suggests I need to gain access to the fan and connector to take some measurements and is possibly my fan motor at fault.

I'm thinking I may have more than one fault. Looking at other's posts have had some heat when their fan stopped but on mine I have no heat at all so can someone tell me if there is a valve that controls the water circulating through the heater/ climate control unit?


A friend has plugged in his scanner and given me the following codes B1922, B1927, B1921

Any pointers will be most appreciated before I lay on my back to gain access to the fan etc in this freezing cold weather?

 

[Artful53]

If anyone can just answer this question it will help please ....

I have no heat at all so can someone tell me if there is a valve that controls the water circulating through the heater/ climate control unit and of thereis one where can I find it?

 

[Davren]

B1922 = Electric Fan Feedback O.C. or S.C. to Ground
B1927 = Climate Control: Cabin Pollution Sensor

I don't know what B1921 refers to.

There is no water control valve for the climate control.
.

 

[Artful53]

B1922 = Electric Fan Feedback O.C. or S.C. to Ground
B1927 = Climate Control: Cabin Pollution Sensor

I don't know what B1921 refers to.

There is no water control valve for the climate control.
.

Thank you Davren for your reply. I have tried to look at the EPER link to see the layout but get an error 666 after I enter my VIN.

I can't understand why I'm getting no heat at all in the car. The climate control remote screen is altering it's display just as though all is working and pressing any button such as up speed or down speed the display responds but no fan and no heat.

Occasionally if I turn the ignition on I can hear the fan going very slow but then pressing up it starts to increase then cuts out?

 

[Muppet1]

Well, it looks like my only option is a new fan if Fiat can supply one or a used 20-year-old one on eBay. Fairly sure its the fan or the PCB that's packed up.

 

[Maxcaddy]

If you have the space, and the enthusiasm, why not buy another 1 or 2 Stilo's in broken order, and you'll have spares forever.

Must say that I have been thinking of doing exactly that myself so I have a good stock of parts that I can change over to see if it makes a difference, and not have to search eBay or pay exorbitant dealer prices.