Clio Auxiliary Heater Fault

I had a similar issue with my Clio (also diesel). It could be a coolant leak affecting the temperature sensor readings, which then messes with the heat control. The car might think it's already warm enough. Did you check for coolant leaks? What does the heat control show?

Interesting. I haven't seen any obvious coolant leaks, but I'll look closer. Where's the temperature sensor located? And what values should I be seeing on the heat control? Any specifics would be great.

I don't know exactly where the temp sensor is; check a repair manual. I didn't go that deep myself. I eventually had the glow plug replaced in a workshop, and that solved it. Considering the stored error, it might be similar. The repair cost about 440€. I'd advise getting it checked professionally to be sure.

Thanks! I'll double-check for coolant leaks and then probably go to a workshop. It turned out the glow plug was defective and needed replacement. Your experience helped me narrow it down quickly. Appreciated!