General Stilo Air Conditioning

[annemt]

ok, i have got a aircon system out of a fiat stilo, and have a few questions if anyone can answer them;

firstly i tried to put direct 12V to the compressor, but it seems to be shorting and not engaging the clutch, what could be causing this as it used to work when it was in the car.

secondly i have read on here that the sensor gets 5 volts in and 3 volts out, when functioning correctly, how could i wire the system up to set off with this 3 volts, i know it will need some sort of relay but not sure exactly how to do it.

if you have not gathered i am trying to get it working WITHOUT the ECU, so i can put it on a different car... any help will be greatly appreciated.

Thanks

 

[Deckchair5]

i tried to put direct 12V to the compressor, but it seems to be shorting and not engaging the clutch, what could be causing this as it used to work when it was in the car.
Where are you putting your connections?

If you're not using a car ECU to control it then you'd be better off not using the Stilo pressure stat as that provides info to the ECU which then decides to
not start compressor (below 10% of 5v)
turn off compressor and start rad fan (90% of 5v)

If you're going back to basics then a more basic aircon pressure stat as used in older cars, running on12v which then feeds a a signal to a 12v relay directly for the compressor clutch would be all you need. With those, if the static pressure is enough it turns the compressor clutch on through the relay and if too high turns the compressor relay off and starts the rad fan with another separate relay

 

[annemt]

Thanks for your reply,

Its the black plug near the pully with two pins in i am putting the power to, one live and one negative, when i pulled it off the car it had another wire bolted to the actual compressor aswell, but not sure if that one is needed.

As for the sensor, will a sensor off a older car bolt streight in the hole or will it need altering in some way.

Thanks in advance.

 

[Deckchair5]

with two pins in i am putting the power to, one live and one negative, when i pulled it off the car it had another wire bolted to the actual compressor aswell, but not sure if that one is needed.

That'll be the problem then as the wire connected to the actual compressor is the earth. So to test it then you connect one wire to the compresor body and another to one of the terminals.

will a sensor off a older car bolt streight in the hole
No idea, they are pretty standard sizes, maybe go to a scrapyard and try it

 

[annemt]

i have give it another try,

i put negative to the compressor body and live to both pins in turn and together; nothing. put live to one pin and negative to the other (with the earth still on the compressor) still shorting, swapped the wires the other way around, the same; still shorting. it does the same with the earth off the compressor body aswell. ??

I have read on here that the feed is 12 volt to the compressor, but when i put the meter on the compressor's black plug the resistance came back as 0 ohms. does this mean the coil that activates the clutch is shorting?

thanks in advance.

 

[Deckchair5]

I have read on here that the feed is 12 volt to the compressor, but when i put the meter on the compressor's black plug the resistance came back as 0 ohms. does this mean the coil that activates the clutch is shorting?
No, a coil is just that, a long coil of wire so it will have virtually zero resistance.

If the clutch coil doesn't energise when you put 12v through it then it isn't working.

 

[annemt]

on the black plug there is 2 wires. i have been putting 12v live to one and negative to the other, this is when it is shorting, it doesn't matter which way i put them. that is without the other earth on the compressor body.

hope that Clarifies what i mean.

Thanks

 

[Deckchair5]

Sure, same answer really, if the clutch isn't engaging when you apply 12v across it then it isn't working

What are you trying to do? Install the whole system in a different car?

 

[annemt]

i just think the coil is shorting out as it isn't engaging the clutch, and the wires are sparking. is there any way of getting the coil off the compressor to check it?

and to answer your other question - yes i am trying to put the whole system in another car.

thanks.

 

[Deckchair5]

It's quite a job
Here's someone replacing a clutch on a Jaguar compressor

http://www.bernardembden.com/xjs/comclutch/index.htm

Putting a whole aircom system into a car that wasn't built for it is extremely ambitious

 

[annemt]

ok,

i have got the AC clutch apart, the clutch its self looks almost new, but the coil is shorting out; where could i just get a cheap coil for one of these?

also thanks for that link for dismantleing the clutch, the stilo one is easier to get apart than that one though.

as for the AC sensor, would a sensor out of a MK1 punto or Brava do?

thanks

 

[Deckchair5]

where could i just get a cheap coil for one of these?
I've no idea. Take some photos and post them up as not many have taken the Stilo compressor clutch apart


Air con pressure stat? It would be sheer luck if they were the same as a Bravo etc. The connector will need to be similar to this. What's wrong with the one you have?

 

[annemt]

hi here is a picture of the pully, clutch and the faulty coil (there are two clips also, (not pictured)).



if you read the full thread i want to get it working in another car without the ECU. - hence the reason for wanting a simpler sensor (if a MK1 punto or brava ETC will do). just the coil is broke aswell.

thanks for any help.

 

[Deckchair5]

Thanks for the pic

You haven't said what car you're trying to install it but a Peugeot 306 aircon stat is a proper switch (unlike the Stilo) and will switch on/off a compressor relay and switch on/off the rad fan relay if pressure goes to high.