Yaris preheating lamp and check engine light

Hey, I had something similar with my Yaris. Is the engine running rough at all when it's cold?

Thanks for the quick response! No, the engine seems to be running smoothly even when cold. Just the preheating lamp staying on, the check engine light, and the smoke. Any ideas?

Ah, ok. Mine was running rough, so it was a different thing. But yeah, preheating issues can be tricky. If you suspect the preheating unit, it might be worth getting it checked out at a workshop.

Thanks a lot for the advice! I took it to the workshop, and it turned out to be a defective preheating control unit, likely due to a faulty connection, just as I suspected. The repair cost me 95€. Appreciate your help!