Air con power/wiring problem?

[ian k]

Hi guy's

I have a problem with my 1.9tdi afn 98 aircon compressor.

When i press the auto or air con buttons on the climate control the compressor no longer switches on.

I have by-passed the single green/yellow striped cable that goes into the compressor from the connector next to the washer bottle direct to the battery and it runs ok.

What i want to know is could this be caused by a dodgy relay and if so which one and where is it please?

The system worked perfectly before the car went into the Audi dealership to get w/pump and cam belt changed november last year.

thanks in advance


ian

[stevie-g-2.6]

have you had\the\system re gassed since it went into the garage?
the aircon compressor wont cut in if the system is low\ on gas.

[Crasher]

I have seen the wiring harness across the back of the rad come away from its retaining clips when the front panel is pulled back into the service position, then it drops onto the belt drive and shorts out, knocking out the compressor.

[ian k]

Thanks chaps

No i have not had it re gassed yet, that was one option i was looking at when reading other threads about the air con.

How will the low level/pressure of liquid in the system stop the clutch from engaging please?

Crasher, i will check the condition of the wiring harness tomorrow

Cheers

Ian

[ian k]

Hi Guys,

Checked wiring harness to air con comp clutch today, seems ok with no chaffing or cuts. I checked electrical continuity from conections to clutch and it also seems fine.

is there a sensor that detects low refrigerant/liquid level that stops the system working? that i can by pass to test or will i have to bite the bullet and go to an air con specialist to check the fluid charge level?

Having studdied other air con threads both here and on other Audi forums it would seem that most air con engineers need to see that the compressor system runs properley before re gassing the system is this correct?

Thanks in advance

Ian

[Crasher]

There is a switch on the condenser accessible with the front bumper cover off. It would have been accessible with the cover on if they had thought about it, it is just out of reach behind the lower right grill.

[roo2002]

I've got the same problem on my 2000 A3 ie no power to the pump.

I had my aircon re gassed today at a friends garage after never having it working since I've owned the car.

Lots of things to try above and just wondered If you ever found your problem ian k

I'll let you know how I get on.

[Zenerdiode]

How will the low level/pressure of liquid in the system stop the clutch from engaging please?

Its there as a safety feature to prevent damage to your compressor. There are pressure switches to measure the charge of gas in the system. Obviously low pressure means there has been a leak or venting of some kind.

But with low pressure comes the very real possibility of contaminants in the system and a low PAG oil charge. Running the compressor in any of these conditions will surely destroy it.