Hi, thank you for contributing to this discussion. In this instance there was no evidence of corrosion or overheating on the blown fuse.
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Yes x100. This is the electrical elephant in the room that people seem to love ignoring.
In the euphoria of FINDING the blown fuse, they overlook the small issue of WHAT made it blow in the first place…
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Hi Speedy, the first thing you do when you have a blown fuse, is replace it. If the new fuse doesn’t blow, what do you do? Obviously the cause of the blown fuse hasn’t been found, nor the problem solved, and I’m sure there is a certain amount of anxiety as the root cause of the failure has not been established. Other than testing all electrical functions what else can you do? What would your suggestions be?? Cheers Phil
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Well, not a case of testing ALL electrical functions.
First thing is to look at the actual circuit in question. Then consider what could have caused the ovecurrent. 9 times out of 10 it will be a short-circuit. If the new fuse hasn’t blown, the fault must be intermittent.
Short-circuit faults are usually caused by defective insulation, and intermittent faults are usually a product of things moving, so I would be looking for locations where wires from the circuits in question are subject to movement, such as where wiring looms have to navigate the jump from frame to handlebars, or where vibration could cause failure by fretting of insulation and movement of the loom.
Once you’ve eliminated wiring issues, you can start thinking about component failures.
It’s just a process of elimination and a methodical approach is usually the key to success.
But just replacing the fuse and thinking that’s the end of the matter usually results in a repeat performance somewhere down the line.
And before anyone says anything, notice my considered use of the word “usually” 
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This has got me thinking.. (ouch). Perhaps not so much the case with a new bike, but don’t forget that an apparent “blown fuse” can also be a defective fuse or fuse holder.
Some of the automotive spade type fuses can fail because of fatigue cracking of the fusible element itself, or vibration of the fuse clips/socket leading to an intermittent connection that is rectified when the fuse is moved during the process of replacement.
If you can actually see the fusible element itself, it is usually (!) apparent whether it has failed under load (blackening, melted blobs on wire-ends, etc.) so something else to think about.
So if the fuse looks OK, worth a continuity check with a light bulb or meter, etc.
Ain’t this fun! 
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I would suggest always check the obvious items first e.g. fuses. When I first got my EV I checked the fuses with what the manual stated and I found that the ECU had the wrong fuse in it (to high an ampage).