Backup buzzer on with key off

The backup buzzer on my 2000 E825 stays on solid when the turf/road switch is left in road and the key is turned off. With the key on the buzzer stays off.
Reverse seems to function as designed: key on, switch in reverse; the buzzer pulses.

Parking brake on?

The parking brake is on, but the key is off.

Update: my bad, the parking brake was off with the key off it will buzz. I see how it works now. I feel like an ■■■■■. :rain: