Citroen C4 Picasso no AirCon and C994 Fault Code

[Andreiva]

Hi,
I was driving today and at some point I noticed the supposed-to-be cool air coming from the car was instead kinda warm. I expected it to return to normal after a while (also had a stop on the way) yet I got back home and it still didn't work so I pulled the Diagbox to read the fault codes and I got a C994 - Aircon compressor clutch control fault.
Since it's usually required, car VIN: VF7**************[VIN obfuscated, can be read by forum staff]
Is this fault code a cut and dry aircon compressor clutch failure and it just means I have to replace this part or could it be caused by something else related to the aircon system?

[mickthemaverick]

It may be a faulty/dirty connector to the compressor. Check you are getting a feed at the compressor and then I'd check the aircon clutch by connecting a supply directly to the clutch solenoid terminal and check that the clutch operates. If not it could be the solenoid failed, if it operates but does not spin up the compressor then it may be a new clutch assembly. That info is based on the C5 system I had and rebuilt, so it may vary from the C4 but the principal is the same. Good luck !

[Andreiva]

Thanks for the info, definitely will have to do some more tests, the only big issue is that the compressor seems pretty hard to reach but I will see how to get around that...

[mickthemaverick]

On the C5 I did the whole job from underneath and found it not too daunting once I got stuck in. The story of that job is on the forum at : viewtopic.php?p=612544#p612544

You may learn something from a quick read through that!!