2008 Concours. Motorcycle battery ok, fob battery ok.
When I push down the key it doesn't disengage the lock nor lights up the screen.
After some research online, mostly this forum and youtube, I was lucky enough to fix it with a screwdriver and lot of electric contact cleaner.
Thank you all for sharing your knowledge. Kind of complicated to name everyone.
The process:
Tap, tap didn't work.
Punching the key (instead of hammering, it seems too much). It worked! That made me think it's that switch, I think some guy was talking on youtube.
Not having the tools to open the ignition actually saved some work, hopefully.
So, I sprayed a lot of contact cleaner into ignition and that ring around it that goes down when you push the key. Use the spare key to see better. Than I pushed away the rubber ring and with a screwdriver I wiggle a bit under the left side pin, the longer one out of four. I presume the magic switch, the G spot is right there: it lighted up the screen! Actually I think I push it down with the screwdriver. Maybe a god trick if you're stranded somewhere. Put back the rubber and done, hopefully for another 12 years. Unfortunately I cracked the rubber in the process.
I just wanted to add: all this started after I rode in a big downpour plus pressure wash after I got home.