Switch that is pressed whilst in 5th gear. Some kind of eco-button for motorways? Never seen anything like it. Just interested y'know

it's a cutoff switch for the gear up indicator on the top left of your clockset, as the 5th is the highest gear there's no need for it to light up in 5th gear

Ahh, bit of overkill for a light but hey ho. Here's me hoping it was some high tech economy shit

I thought that it switched on the flux capacitor!