Player controlled prefab not moving in new Scene

So I started working on a vehicle object in a scene. It is a gameObject with just a script attached, along with some children (Model and Camera). I got it working to an acceptable point when I wanted to test it in another scene, so I dragged the gameObject into my prefab folder, made a new scene, and dragged the prefab back into the scene. Everything looks okay, except the vehicle has stopped moving. Here’s the code I’m using to move the thing:

this.gameObject.transform.position = this.gameObject.transform.position + (currentVelocity * Time.fixedDeltaTime);

In the debug window, I can see that the velocity vector is in fact behaving as expected, it’s just not having any effect. I’m also using

this.gameObject.transform.Rotate(0,(turnSpeed * turningState * Time.fixedDeltaTime),0);

to rotate the thing, which is actually working totally fine, so I’m pretty confused. Also, all of this code is in fixedUpdate.

It was in fact FixedUpdate. I found out the problem was just a silly mistake on my part. I was using this plotting thing to chart out my velocity. However, for it to work it needs its plotter object in the scene, which I forgot about in the new scene. So it was breaking on the line right before I moved the object, when I was getting the velocity plotted. I guess I was too busy expecting Unity weirdness to look at my own code!