when I put the fuse in to switch to 2wd, car wont leave 1st gear.

What is your question?

In the summer I put in the AWD fuse (under the hood) to switch to 2wd. Well I've had some real bad work done on this vehicle (they told me they pulled the engine to replace the radiator), now when I put the fuse in the vehicle wont shift out of 1st gear (automatic). I cannot find any mechanic that has ever heard of this. The dealer wants 2500$ up front to do a diagnostic. Can you shed any light on this?