Ka auxiliary heater issue

Sounds frustrating! I had a similar issue with my 2018 Opel Corsa. The symptoms were a little different, but the error codes pointed towards a heating problem. Have you checked the glow plugs for the auxiliary heater? Those are often the culprits. A defective glow plug won't ignite the fuel in the heater, and that shuts the whole thing down.

Glow plugs, huh? I've heard the term but don't really know what they do. Are they easy to check myself, or am I better off taking it to a garage? And if it IS the glow plugs, is it a pricey repair?

Glow plugs are basically like tiny spark plugs that heat the air to help the fuel ignite, especially in cold weather for diesel engines. As for checking them yourself, it depends on your comfort level with car maintenance. You'll need some basic tools and a multimeter to test their resistance. Honestly, if you're not familiar with electrical testing, it's probably best to take it to a workshop. Regarding cost, it's not usually bank-breaking, but it depends on the labor involved. It cost me 440€ to get it fixed. They will also check the heating system, blower motor, climate control, temperature sensor, and the heater core

Thanks for the advice! Took it to a local garage, and you were spot on – glow plug for the aux heater was indeed kaput. Cost me 440€ in the end, but at least it's sorted now. Appreciate the help!