General Location of Air Con Relay

[MWalsh]

I am wondering if anyone can point me in the right direction please? I have a 2009 Ducato 3.0L 160. The air con is not working. The belt on the compressor is fine as is the fuse. Am trying to locate the relay. Is it in the same ares as the fuse is? F19 7.5A.. There are many relays here but don know which one I am looking for..

 

[Popitinpete]

I am wondering if anyone can point me in the right direction please? I have a 2009 Ducato 3.0L 160. The air con is not working. The belt on the compressor is fine as is the fuse. Am trying to locate the relay. Is it in the same ares as the fuse is? F19 7.5A.. There are many relays here but don know which one I am looking for..

Is there gas in the system? If its leaked out the low pressure switch prevents it coming on and burning out the compressor. Get a leak/vacuum test.

 

[Mike1alike]

Also, if the air con pressure sensor is not working, no voltage is given to the compressor.

 

[MWalsh]

Is there gas in the system? If its leaked out the low pressure switch prevents it coming on and burning out the condenser. Get a leak/vacuum test.

Hi, thanks for reply. Yes, the gas is fine was checked and pressure test done.

 

[MWalsh]

Also, if the air con pressure sensor is not working, no voltage is given to the compressor.

Thanks, is there a way to test the switch? Would you know it’s location?

 

[Popitinpete]

Hi, thanks for reply. Yes, the gas is fine was checked and pressure test done.

OK, that's good news, as Mike says could be the low pressure switch or feed to the switch but I'm afraid I've no idea exactly where it is on your model but if you follow the air com pipes back from the compressor to the cabin its usually on the feed pipe from the compressor. Not sure it can be checked but replacing it and crossing your fingers means the freon needs to be removed and then obvs filled back up. It's a specialist system, if it's nothing as simple as no feed to the switch or the switch connector fell off it may well be the safest option to take it to a professional unfortunately

 

[Mike1alike]

I know it's location on Punto, but there are not many differences on different Fiat models in this subject, I think. So, at Punto it is on the air con condenser, downwards and is easy to spot by the electrical cable attached to it. I think that you could see with a tester connected to the car, if it is working. If it is, you will get the actual reading of the pressure. Otherwise, I'd say that the best way to solve it is to go to an air con specialist/garrage and they could probably test the sensor. And if the tester is broken and needs replacement, you can do it yourself because there is a valve that closes when you take the sensor down, so no freon will get lost.

 

[Popitinpete]

I know it's location on Punto, but there are not many differences on different Fiat models in this subject, I think. So, at Punto it is on the air con condenser, downwards and is easy to spot by the electrical cable attached to it. I think that you could see with a tester connected to the car, if it is working. If it is, you will get the actual reading of the pressure. Otherwise, I'd say that the best way to solve it is to go to an air con specialist/garrage and they could probably test the sensor. And if the tester is broken and needs replacement, you can do it yourself because there is a valve that closes when you take the sensor down, so no freon will get lost.

Condensor? Did you mean compressor? Condensor is under the dash next to the matrix

 

[Mike1alike]

Condensor? Did you mean compressor? Condensor is under the dash next to the matrix

Nope, I mean condenser, the one that freon condenses in. Is attached near the car's cooling system radiator, I think people call it air con radiator.
That's the one:

 

[Anthony489]

Hi MWalsh

Here is a description of the AC and some schematics and Fuse/Relay location diagrams. Several Fuses affect the AC. Also, the cab fan must be switched on before the AC will operate.

Manual Climate Control

The climate control system control unit H080 receives an INT ignition-controlled supply at pin 1, via the line protected by fuse F51 located in the junction unit under the dashboard B002 and, at pin 4, from the direct battery line protected by fuse F39 of B002 via pin 17 of connector A of the Body computer M001.

Also, the H080 control panel is connected, via pin 6, to the air conditioning unit earth C016.

The function of switching the air conditioning on is managed by pin 2 of the climate control system control unit H080 which sends a request to the engine management control unit M010 (pin 54 of connector B) The same signal is sent, depending on the version, either to the conversion socket or to the additional air conditioning system, if present.

The climate control system control unit H080 receives feedback, at pin 3, that the passenger compartment air fan N085 is turned on. The speed of the latter is regulated via the fan control H081 which, through the adjustment resistances O030, makes it possible to earth the fan motor through different resistance values, thereby allowing the adjustment of the speed.

The passenger compartment air fan N085 receives a direct battery supply, at pin 2, via the line operated by relay T08 (except during starting) and protected by fuse F08 located in the engine compartment junction unit B001. The passenger compartment air fan control H081 is connected, via pin 1, to the air conditioning unit earth C016. The climate control system control unit H080 is backlit, via pin 5, when the side lights come on.

Compressor Engagement

Relay T05 of the engine compartment junction unit B001 controls the compressor L020 engagement circuit. The power supply for the relay arrives via the direct battery line protected by fuse F19 of the engine compartment junction unit B001. The direct battery supply for the compressor relay T05 coil arrives directly from relay T09, also located in the engine compartment junction unit B001 and controlled by pin 72 of connector B of the engine management control unit M010. The engagement request is sent, from the climate control system control unit H080, to pin 54 of connector B of the engine management control unit M010.

 

[MWalsh]

Thanks for all the reply’s and great advice. Much appreciated.

 

[Popitinpete]

Nope, I mean condenser, the one that freon condenses in. Is attached near the car's cooling system radiator, I think people call it air con radiator.
That's the one:

Sorry my mistake, I was getting mixed up with my condensers and evaporaters. It's OK I've only been an air con engineer for ten years....