Laguna Climate Control Failure

I actually encountered a comparable problem with my old BMW a while ago. Though it was a different brand, the symptoms you describe sound very familiar. The climate control acted erratically and then failed entirely. Did the error code specify which sensor it was, exactly?

That's interesting! The error code just said 'interior temperature sensor'. I've checked the wiring and plug connection, and it all looks fine. Could it still be a faulty connection even if there's no visible damage?

Even without visible damage, a faulty connection is still quite probable. The cables can be damaged on the inside without showing signs of it on the outside. But without proper testing and measurements of the sensor readings you risk only replacing parts. Given the error code and your symptoms, the most cost-effective solution for you is to take it to a workshop.

I took your advice and went to a mechanic. Turns out you were right, it was a damaged cable! They replaced the wiring harness and the sensor, and now the climate control is working perfectly again. Total cost was 95€.