MPPU Tilt C - Error 4245 Advantx system would not boot correctly.

MPPU Tilt C - Error 4245 Advantx system would not boot correctly. The MPPU would continuously reboot with error 4245 displayed on the Advantx console. The problem would correct itself after a variable time between 2 and 15 minutes(Generally 3 mins). Once the fault was gone, could not be reproduced unless the system was switched completely off for 2+ hours. Sometimes OK up to one week, then fault reoccurs. Customer would leave the system until it came right, or reboot which sometimes also had the same effect.