[snic]

I'd definitely check the F3 fuse (non-walk-home). But that can't explain the coolant leak. All you can do, I think, is run the engine with the hood open and see if you can spot the leak.

 

[snic]

I always thought when the F3 fuse blew the car would not operate. I'll definitely take a look!

In that case it would be the "Walk Home Fuse"...

 

[snic]

No, the engine will not overheat if the fuse is blown.

Yes it absolutely will overheat if F3 is blown. After it blew in my Volt, the engine was running at 230-250 degrees at highway speeds, and eventually I got an "engine not available" message. After I replaced the fuse, the temperature never rose above about 215, usually it was around 200. There is plenty of documentation of this (which unfortunately I hadn't paid much attention to until after the fuse blew, which is why I was driving with such high coolant temps - I should have immediately replaced the F3 fuse and unplugged the EGR as soon as I realized the F3 was blown).

The OP of course has a different problem than the widely reported EGR valve blowing the F3 fuse causing high coolant temps, as his F3 is intact.