Problems with heating/cooling and air conditioning in Renault Laguna Diesel 2012 - advice and workshop experience wanted

Hello, I'm not a car expert, but I've had similar experiences with my 2014 Renault Megane. In my case, the air conditioning control unit was defective - more precisely the control unit, which unfortunately was not so easy to repair. It had to be completely replaced. I had it done at my regular garage and it cost me around 880 euros including labor. That's my experience, but of course your problem could have a different cause. Could you tell us a bit more about the symptoms? When exactly does it occur, what about other functions? The more information, the better I (and others here) may be able to help you. I hope this helps you a little!

(Translated from German)

Hi, thanks for your quick reply and the information. It could of course be the air conditioning control unit, but somehow I have the feeling that it could be something else. It's just really difficult to assess when you have no idea yourself, you know. I can tell you that I'm at about 131380 km and the last service was only a few months ago. Everything should actually be in order. Do you have any ideas about what I could check before I go to the garage? Maybe I can prevent the worst from happening. Anyway, thanks for your help!

(Translated from German)

Hey, sure, no worries, I'm happy to try and help! I'm not 100% sure though, because like you say, it could be a lot of things. When you say the last service was only a few months ago, was the refrigerant pressure checked then too? Incidentally, this is very important for the functionality of the air conditioning system. If the pressure in the refrigerant circuit is too low, this can result in the air conditioning system not switching on. In this respect, a refrigerant leak could also be a problem. You could check this or have it checked in the workshop. Possible electronic faults could also be the cause, e.g. sensors that are not working properly. However, this is difficult to check yourself without special tools or connecting the car to a diagnostic tool. I hope this helps you a bit, otherwise I wish you good luck with your troubleshooting and hope it's nothing too serious! Let me know when you know more. And don't let the garage pull the wool over your eyes, unfortunately that's part of it.

(Translated from German)

Hi, really great that you replied so quickly and in such detail, thank you! I hadn't thought about the refrigerant pressure before, that could actually be the problem. A refrigerant leak would of course be really bad and could be expensive... The sensors and electronics also sound plausible, so I'll definitely keep an eye on that when I go to the workshop now. Of course, it would be cool if I could check it myself, but I don't think it will be possible without the right equipment. So I'll take care of it in the next few days and then take it to the workshop. Let's hope it's nothing too bad and that everything can be sorted out at a fair price. Thanks again for your help, that was really nice! I'll let you know when I know more. Take good care of yourself!

(Translated from German)