What was found
INSPECTION TYPE-N/A, DURING CABIN CLIMBOUT AT 18,000 CABIN PRESS BEGAN CLIMBING ABOVE 9,000 FT THE CABIN ALT WAS SET AT 6,000. THE AUTO FAIL LIGHT ILLUM AND PRESS DIFF WAS 8.4 APPROX 2 MIN LATER CABIN CLIMBED ABOVE 10,000 AND PRESS RELIEF VALVES WERE CLOSED AND THE UPPER PRESS RELIEF VALVE LIGHT REMAINED ON. DESCENDED BELOW 10,000 FT W/OUTFLOW VALVES OP. REPLACED AUTO PRESSURE CONTROLLER BITE CHECK OK.