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Discussion Starter #1
Does anyone know where I can find some info about which Relay does what ?

My AC fans are not working, hence no AC and I want to check if there is a relay which might be faulty.

cheers
 

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AC fan is the same as the regular fan, does that work if the engine gets hot? if so, you're looking at low pressure in the ac system most likely (ie no more gas).

The special button ("AC") on the climate control system control unit switches on the air cooling and dehumidification circuit, activating the air conditioning compressor.
The above button enables the operation of the air cooling circuit, but the actual compressor activation is also dependent upon the activation of:
- the linear sensor, located on the coolant circuit that stops air conditioner activation if coolant pressure is too low or high;
- 'frost" sensor on the evaporator, that temporarily deactivates the compressor if temperature drops to 0°C, with risk of "frost" on the evaporator.
- the engine control unit that excludes compressor operation in accordance with engine management logic; e.g. in the case of high engine temperatures or high engine load (sudden acceleration);

no relay found, the sensor on the ac pipes informs the engine control unit what to do.

the cooling system:
The radiator and air conditioner condenser cooling system consists of two electric fans operated at two different speeds, by means of a series/parallel connection:
- the first speed is activated at an initial engine coolant temperature level or a certain air conditioning refrigerant fluid pressure;
- the second speed engages at higher temperature or pressure levels.
The fans are operated by three specific relay switches, two located in the engine compartment control unit and one located directly on the radiator.
The supply line for the fans is protected by two special fuses, located in the engine compartment junction unit

relay T06 and relay T07 in the underhood box
 

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Discussion Starter #3
Thanks for the awesome info Cuore Sportivo !!!

To be honest I really do not know if the fan turns once the engine gets hot. This is because I have never driven it in traffic or for long periods of time. To understand I purchased the car in 2005 and still has 5K Miles only !

I will start her up and leave her untill the temp rises to a point that the fan should turn on.

As regards to gas, when I press on the re-fill nipple I hear a hiss coming out which sounds very pressurised.

So ill see if the fan turns on, and if it doesn't its the fan relay.

Meanwhile I appreciate your useful info :thumbup:
 

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Discussion Starter #4
Let the car run and the fans did work.

I hear the click sound when I press the AC button and hear a hiss sound coming in from the dash but warm air.

I will therefore need to check if there is enough gas.

Since I hardly use the car I cant imagine that there is a loss of AC gas but then again the less you use a car I suppose the more problems like this you get !
 

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hiss sound from the vents means low on gas.

Mine was low after 1 year aswell, refilled it myself and has been fine since. I think they don't quite fill the system properly from the factory.
 
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