As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
LEFT AC BUS ILLUMINATED UPON CLIMBOUT AFTER TAKEOFF. QRH COMPLETED AND VERFIED CONDITION COULD NOT GET BACK ON LINE. AIRCRAFT RETURNED TO MSP. MAINTENANCE CLEANED CANNON PLUGS ON LEFT AC CONTACTOR BOX AND REPLACED LEFT AC GCU. OPS CHECK GOOD.