Hey All.
I too, had a similar issue on my 2012 xterra, but my solution, after 4 hrs of mucking about, was something so simplistic (and stupid) that I have to share. Here is hoping you can avoid hours of new and colourful language, with my experience.
So my symptoms were:
Power to dash
lights, radio etc all working
Battery good.
No click just nothing on key turn.
What I did:
Charged and checked battery (all good)
Check alternator output (Jumped/bump started) (all good)
Checked clutch switch (all good)
Check every @#$'n fuse there is. (all good)
Pulled starter and bench tested (all good)
Re-installed starter and jump tested in place (all good; engine turned; should have done this in the first place)
Cussed, stomped my feet, and cursed the auto gods and Nissan engineers .
Broke for lunch
So I regrouped.
I decided to get under the foot well, pull the clutch switch out and test it properly (Used a paperclip earlier, and I wasn't confident on the result). Tested the switch and all was, you guest it, good. It was at that point with my head buried under the steering wheel, that I observed a second plunger switch. I depressed the clutch all the way and the button on the switch passed right through a hole in that clutch pedal assembly. Yes, this is where I had my epiphany and experienced the "oh ffs" moment. I looked on the floor mat and there it was...a grommet that had warn through and fell off, leaving nothing to activate/deactivate the switch. [insert more cussing]. With the vehicle out of gear (manual trans), i depressed the plunger switch with my finger, and turned the key...she started. This is where the auto gods and the engineers at Nissan would have felt their ears burning with the me commenting on the design of the clutch peddle assembly (some cussing may have been included, but I can't recall).
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So, I just happen to have saved a few body work grommets from our Isuzu Rodeo and one fit perfectly in place of the one that broke. What a stupid design.
Anyway, should you have a similar experience with a no engine start scenario, have a quick look at the little rubber stoppers that engage the clutch switch(S) and particularly the one in the back, against the firewall, to see if is still there. Best of luck!
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