ABS Warning light... but no code present

My '00 Jeep Grand Cherokee WJ Laredo 4.0L V6 (140,000 miles) starts fine and the lights on the instrument cluster cycle through as normal... but at approximately 15 miles per hour my ABS Warning light comes on and stays on.

I've run multiple scans (including live data) but get no code.

Brake fluid is full. I replaced all four wheel speed sensors about a year ago when one broke during a full front clip replacement, so they're essentially a new set throughout. Full set of brakes and calipers replaced about 4 years ago.

Thoughts? Suggestions?