My 2003 Octavia air con unit is cooling intermittently. I have gone to an air con specialist but he can’t trace the entire fault. What he did say was without leaving the car to his (his not familiar with the car system) is that

1. The gas is sufficient

2. The compressor is working

3. The compressor is not getting power

4. The switches in the panel seem to work fine

So the problem is from the switches to the compressor. What are the common problems for the air con unit in this model? Anyone can help?

Is this heating and air conditioning system, or the "Climatronic" Climate Control system? In the latter case it sounds like it's working normally.

I believe it is a heating and air conditioning system. The console does not have climate control functions. Just Cool/Heat dial, blower speed, direction dial and two buttons for air conditioning and air circulation

The cooling fans in the engine bay will only work when required, previous cars ive had with AC kept turning the fans on and off as they were needed.

Try a scoosh of Servisol on the contacts at the compressor and in the instrument panel then. If that doesn't work it's down to playing hunt the intermitttent break in a wire and good luch to you!

I have a friend with a Golf who has exactly the same problem. I've checked the fan relay and that's OK. I'm now along the lines of thinking that the fault is either the pressure sensor or the temperature sensor, but as yet it's not fixed.

Please post back if you find out what the problem is......

Justy a long shot idea:

What about a loose nut holding the compressor clutch to the compressor shaft?

This is notorious problem that is usually identified when the assembly comes off and is found on the under-tray. Worth a peek at least. [Make a search on the forum for more details]

What about the external temp sensor, mine had a bit of hissy fit a while back and was insisting the outisde temperature was about 10 degrees when it blatantly wasn't and the air con wouldn't run cold. After a couple of minutes it suddenly went back to normal and cold air started coming out the vents. this was on a car with climatronic though so I don't know about the other versions with air con.

I 've gone through the wires and contacts. Everthing seems to be fine now however... being an intermitttent problem I am hoping the problem does not occur again. The next thing on the list would be the temp sensor. I am handy with my hands but without the workshop manual, its a bit of a hassle tracing the wires.

The problems still there however I noticed that prior to the air con failing, the fan motor or the air flow slows down.

There also seems to be alot of foam (i belief the issulation foam with the air con unit) getting blown out. I am now wondering if the air con or the sensor is clogged up.

Solved the problem. Sent it in. The Aircond Control Module (s ij0 919 506 K) was at fault.Cost me abit but ok.