2003 supra launch SSV speedo light

Figured I would post here even though it is a Supra. I tend to stick to the moomba forum since my first boat was a moomba. Here's the problem.

Just noticed when I was working on the boat last night that my speedo gauge light comes on when the key is turned on. So it is always on if the key is turned in the boat. All the rest of the gauge lights come on when u turn on the nav light switch. Just wondering if its suppose to be like this. Speedo light will not come on when nav light switch is on but key is off. I hardly use the boat at night so I have never noticed it.