What was found
PRESSURIZATION CONTROL EICAS MESSAGE CABIN ALTITUDE SHOWN. CABIN ALT & CABIN ALTITUDE LIGHTS ON. COULD NOT CONTROL THE CABIN PRESSURE IN THE MANUAL MODE (DESCRIBE CAUSE OF DEPRESSURIZATION , IF KNOWN) TALKED TO THE CREW AFTER LANDING AND THEY TRIED BOTH AUTO 1 AND AUTO 2 WITH NO HELP FOR CONTROLLING CABIN ALTITUDE. THEY DIDNT T RY MANUAL MODE. DID NOTICE THE CABIN PRESS SELECTOR PANEL RATE W AS ALL OVER THE PLACE IN THE GATE. BITE CHECKED BOTH CPC''S AND N O FAULTS NOTED ON BOTH. SUSPECT CABIN PRESS SEL PANEL. REPLACED CABIN PRESSURE SELECTOR REF. 21-31-01. PERFORMED CPC #1 AND #2 BITE, NO FAULTS DETECTED, REF. AMM 21-31-00-705-085. PER FORMED CABIN PRESSURE MANUAL CONTROL TEST, NO FAULTS, REF. AMM 2 1-31-00-715-001. PERFORMED CABIN ALTITUDE FAILURE INDICATION TES T, REF. D(1)-(5), NO FAULTS, REF. AMM 21-31-00-735-023 ROTABLE PARTS CHANGE WAS INDICATED - TT # 1308497 SN OFF 0863 PANEL, PRES, CT OFF 99-2131-9-0005 0863 ON 99-2131-9-0005 0197