Expert auxiliary heater problem

Interesting. I had a similar problem with my Expert. It wasn't exactly the same, but the symptoms sound familiar. Have you checked the glow plugs? Sometimes a defective glow plug can cause issues with the auxiliary heater.

Glow plugs, huh? I hadn't thought of that. Where exactly are they located, and is it something I could potentially check myself, or am I better off taking it to a mechanic? Is it a difficult job to do? I'm decent enough with tools.

They're usually located near the heater unit itself. Honestly, while you could technically check them yourself with a multimeter, it can be a bit fiddly if you're not familiar with auto electrics. Given the error code and the fact it's the auxiliary heater playing up, my advice would be to take it to a trusted workshop. I eventually had to do that and they found it was a faulty glow plug and some minor coolant leak. They fixed it and it cost me around 440€.

Thanks for the advice! I'll get it booked in at a local garage then; sounds like it could be the glow plugs, like you said. Hopefully, it's a relatively simple fix. I appreciate the help!