The Galaxy, Sharan and Alhambra AC system isn't known to be exactly robust! It's becoming increasingly rare to see a Mk2 with a working AC system which is a shame because its normally down to a very small leak which allows the gas to escape over a prolonged period.

Frequently, we hear people saying they have been to have the system topped up only for it to stop working again in a few weeks which is annoying because that's a waste of time, money and gas! The main trouble is that AC testing kits rely on creating a vacuum to test whether the system has any leaks however the Galaxy leaks so slowly that the system doesn't detect it and therefore many AC specialists say its fine and fill it up.

It is fortunately quite easy to test though as generally the system is well sealed and there is only one site where it leaks from and this is at the top of the receiver drier cap. The receiver drier has a service interval of 2 years so if this was followed then the cap would be replaced and not leak however the reality if that it is very rarely replaced and therefore corrodes to allow gas to leak.

There are other topics that discuss replacement of the condenser so familiarise yourself with those if you don't know where it is or how to access it. Once you can see the top then remove the top cap, early models have a simple push on over cap, later models have the overcap bolted down but either way once that is removed then we can see the top of the receiver drier unit.

Fill the top with some water or, to make it easier to see, some window cleaner and check for escaping bubbles. In this video you can see the gas escaping from the right side every second or so. Once confirmed you can dry the cap top and decide if you want to replace the dryer and cap or the whole condenser Link