As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) ON TAKEOFF ROLL, ENGINE OIL PRESSURE LIGHT AND ECAIS OIL PRESSURE LIGHT CAME ON. TAKEOFF WAS ABORTED. INVESTIGATION FOUND OIL PUMP SCAVENGE PUMP DRIVE SHAFT SLIPPED OUT OF THE SPLINES DUE TO IMPROPER INSTALLATION. SERVICEABLE PUMP AND DRIVE SHAFT INSTALLED.