Living la vida loca!
AO Silver Member
Join Date: Jul 2005
Hi, the compressor doesn't have a fan. The condensor (smaller radiator in front of the main engine radiator) uses the same fan as the engine. When the a/c needs to reduce pressure, the pressure switch will tell it to switch on at a low speed. When the engine needs it to cool the radiator, it will send a signal via a heat sensor on the thermostat and tell it to run at a higher speed (via the ecu). The engine always having preference over the a/c. When the car is at speed, generally there is no need for the fan so if your a/c is running OK at speed, it could be a way to diagnose the fault a little further. Works OK at speed = bad pressure switch/bad low speed resistor/..... If it does not work at speed, could be compressor. As far as looking for the compressor, it sits low down and has two pipes sticking out of it. One runs to the condensor, the other runs to the back of the engine (dryer/filter, evaporator, etc...). But there is not much you can do to a compressor other than listen to it, see if it clicks into action or not. Also, when diagnosing a fault, always have the cabin temp at the lowest possible setting (forcing the a/c on regardless of cabin temp). A faulty temp sensor in the cabin can also be at fault. Some climate controls come with a self diagnosis function but ultimately, best way to check sensors, relays, etc, is by having the a/c diagnosed by a specialist with the Alfa tester.
By the way, 80c at speed could be the start of a faulty thermostat. Not critical to run at 80 (my 156 is now getting like this) but anything lower is a faulty thermostat (usually).