I checked, but the light stays on regardless of PTO lever position. I tried it in N, 1, 2, 3 and 4. Also, fluid level looks perfect. Maybe the sensor is bad, hard to tell since I don't know what it is sensing.
I figured out the crazy light. It is a diff lock indicator. It is mechanical with a ball detent. Looks like the first time I used the lock, the ball went in, but never came out.