Corsa Climate Control Issue

I had a similar gremlin in my old Renault Megane. Drove me nuts! Check the temperature sensor wiring and electrical connectors first. It could be a break in the wiring harness causing your symptoms.

Whereabouts exactly on the Corsa did you find the dodgy connection? Was it obvious or buried deep?

On the Megane, it was near the blower motor resistor, a real pain to get to. Honestly, with those symptoms, and if you suspect wiring, it might be quicker to have a workshop take a look before you chase your tail. Best of luck.

Took it to the shop this morning. You were spot on - defective plug connection. 95€ and it's sorted.