Tail Light And License Plate Only Illuminate With Key In Park Mode.

I've just purchased a 2010 Bonneville SE and find that the lights don't seem to operate correctly.
I'm searching online for a wiring diagram of the bike but only find spam/clickbait type links.
Call me insane, but I'm thinking I would have a go at checking out the wiring myself before taking it to the dealer.

 

I appreciate the direction. I will spend some time in the Newbie section for sure. As well, I'll provide more details.

This is an amazing group with solid engagement, so I vow not to take it for granted!

I'll follow up soon.

 

Bulb position? Forgive me, but what is meant by that? Is it the tail light bulb?

For clarification and additional information...
The issue is that the Tail Light And License Plate Only Illuminate With Key In Park Mode. Brake light operates/illuminates normally.
I have only acquired this bike, and almost immediately installed a tail tidy with LED light.
It was only when the LED was installed that I noticed the issue. I then disconnected the new unit and reconnected the stock unit. The issue remained. Taillight is not lit up unless in the key is in Park mode.

 

Ok, Thank you!

 

UPDATE: TheParking bulb in the headlamp is working fine. It does come on when the key is in Park, but the issue remains that taillight illuminates ONLY when the key is in Park.
Night riding is still not an option.

 

2nd Update.

Firstly, THANK YOU! for all your responses and comments. Very helpful. In particular, the wiring diagrams that were shared. That was the key to figuring this out!

The problem is solved. It was a fuse! (#8 to be exact) The odd thing about the tail light is that it has two fuses running to it! One for the brake light AND park light, and a separate one for the running light.

So much embarrassment when it ends up being such a simple solution!

Again, thanks for the support. I look forward to engaging and contributing more going forward.

Happy riding all!