It looks like you solved the problem about six weeksa ago, but...
I had this one SP3020-30, intermittent code 24, 41, etc., but especially 24, for the longest time. Truck had new F/R contactors. Troubleshooting did not find problems with contact tips, coils, wiring, cables, motor, etc. Blamed problem on unsatisfactory battery condition. Batteries were serviced, but the machine still had problems. One day traction fuse blew. Changed fuse. Have not heard of trouble on that machine since. Now I make extra certain to check fuses for voltage drop under load first before I start busting my brain looking for problems that aren't there.
Your results may vary.