Swiftwater Z06

At the track for the first time in a few months. Warm day (95 degrees) but not pushing real hard (oil temp 225, oil pressure good 50-60). Any ideas why this code might have been set? It has happened a couple times before but has cleared itself after the car sat for a few hours. This time a friend cleared it with an OBD II scanner which only gave the code number and no other info.

Would appreciate any suggestions. Thanks!