Skoda Yeti Diesel Preheating Issue

That sounds like a pain! The preheating system on these modern diesels can be a headache when they go wrong. A constantly lit preheating lamp and the check engine light are definitely not ideal, and smoke is not good. Given the mileage, and the fact it's a 2017 model, I'd be tempted to check the simple stuff first. Any signs of rodent damage to the wiring around the preheating control unit? Have you had a good look at the plug connection itself for any corrosion or damage?

Rodent damage, you say? I hadn't even considered that! Where exactly is the preheating control unit located? And is there a way to test the plug connection without just poking around?

The preheating control unit is usually tucked away somewhere near the engine block, often near the battery or the ECU. Tracing the preheating lamp wiring might help you find it. As for testing the plug, a multimeter would be your best bet to check for continuity and voltage. However, working with car electronics without the right knowledge can be risky. Honestly, with those symptoms, especially the smoke, it might be worth getting it checked by a mechanic. It sounds like you're on the right track with the connection idea, but a diagnostic check could pinpoint the exact problem and save you a lot of hassle.

I wanted to thank you for pointing me in the right direction! It turns out it was a bad connection, just like you thought. 95€ later and it's all sorted! No more smoke when I accelerate!