JD 50d sys code

Bought a new to me 2005 jd 50d that got delivered yesterday. Drove for about 20 minutes just messing around and as I was parking it, it throttled up and would not respond to any throttle inputs followed by a SYS light on the dash which stayed on, not blinking. There’s very limited info online but I read the frequency of blinks or staying solid meant different things and this was a throttle fault indicator. I started it this am and the throttle operated fine for a the couple minutes I had to try it. I won’t be back at my farm till Sunday to mess with it but was wondering if anyone could shed some light on this code. Thank you