As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CLIMBING THROUGH 4000 FEET CABIN SEL MAN FOLLOWED BY CABIN RATE LEVEL 1. CABIN PRESSURE WOULD NOT STABILIZE INITIALLY IN MANUAL MODE. CABIN WAS INDICATING -5000 FEET . RETURNED TO INDY AND GOT THE CABIN TO STABILIZE ON DOWNWIND MANUALLY. SHGN 12JUL23 04:05 IND U NRR: NO REFERENCE REQUIRED REVIEW OF CFDS SHOWS BOTH CPC'S FAULTING MOTOR/OFV. REMOVED AND REPLACED CABIN OUTFLOW VALVE ACTUATOR IAW AMM 21-31-20-2. OPS CHECK GOOD.