Beat Engine Mount Error

That sounds familiar! I had a similar uneven idling issue with my old Opel Corsa. It turned out to be a failed motor mount – what you're calling an engine mount. Motor mounts are like the shock absorbers for your engine. They're rubber and metal pieces that bolt your engine to the frame. They absorb engine vibrations to keep your ride smooth. You are getting an error code, and the engine is shaking, so it could be what you suspect, yes. Is the error code specific, or is it just a generic 'engine mount' error?

The code reader wasn't super specific, just pointed to the engine mount. Is there any way to tell for sure if it's the mount itself, or still a wiring issue without tearing everything apart? Could I visually check the mounting bracket for cracks or something?

Visually inspecting it is a good start! Look for cracks or tears in the rubber part of the mount, excessive movement when the engine is running, or any signs of fluid leaking (some mounts are fluid-filled). But honestly, with those symptoms and the error code, it's probably the mount itself. It's not an easy job to replace yourself unless you have some experience, so you might want to have a workshop take a look. They can confirm the problem and give you a quote for the repair.

I took it to a local workshop, and you were right, the engine mount was indeed defective. Apparently, the cable or plug connection of the component was also defective. They're quoting me 95€ for the parts and labor. Not thrilled about the cost, but at least I know what the problem is now!