Narrative:

I worked aircraft X at the south end of ZZZ airport. There was little airport lighting in the area at that time. I worked MEL 21-7. Vent avionics sys fault. Changed the skin air outlet valve ended up being no fix. Per MEL procedures I deactivated the valve in the closed position with the internal flap in the open position per aircraft maintenance manual (amm). But it was hard to tell the difference between when the valve is in the closed position and the internal flap is in the open to 45 degrees position and there was also no amber xxx on cabin pressure page with deactivation switch in the off position during fr evacuate/evacuation procedure. Lack of knowledge of how exactly the valve was supposed to respond after complying with amm. It was also hard to verify the difference between where the valve is in the closed position and the internal flap is in the open to 45 degrees position. There was absolutely no way to physically verify that the position of the valve was completely closed and locked other than press on it. Which all would do would be seat it in place. Pushing on the valve would only seat it back in place with no slack or movement to help with the verification. Even physically verifying the flap 45 degrees to open was physically impossible. The difference of when the smaller flap open to when the larger flap closes was by turning a lever and back it off. It does not move then backing it off to store the lever in the flush position. Lack of knowledge to document reactivate and deactivation of valve per MEL 21-7 on log page or non-routine which was all just lack of knowledge.lack of resources. I was working remotely from the south end of the airport without a computer to verify my work and lack of proper lighting for verification process. Stress because of these factors plus pressure management to clear MEL.add to the MEL fr process to visual check the skin air valve is in the full close position; flush fuselage skin.

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Original NASA ASRS Text

Title: An A320 Mechanic reported being unable to clear an MEL item; and then improperly re-deferring the valve due to time pressure and inexperience.

Narrative: I worked Aircraft X at the south end of ZZZ airport. There was little airport lighting in the area at that time. I worked MEL 21-7. Vent avionics sys fault. Changed the skin air outlet valve ended up being no fix. Per MEL procedures I deactivated the valve in the closed position with the internal flap in the open position per Aircraft Maintenance Manual (AMM). But it was hard to tell the difference between when the valve is in the closed position and the internal flap is in the open to 45 degrees position and there was also no amber xxx on cabin pressure page with deactivation switch in the off position during FR EVAC procedure. Lack of knowledge of how exactly the valve was supposed to respond after complying with AMM. It was also hard to verify the difference between where the valve is in the closed position and the internal flap is in the open to 45 degrees position. There was absolutely no way to physically verify that the position of the valve was completely closed and locked other than press on it. Which all would do would be seat it in place. Pushing on the valve would only seat it back in place with no slack or movement to help with the verification. Even physically verifying the flap 45 degrees to open was physically impossible. The difference of when the smaller flap open to when the larger flap closes was by turning a lever and back it off. It does not move then backing it off to store the lever in the flush position. Lack of knowledge to document reactivate and deactivation of valve per MEL 21-7 on log page or non-routine which was all just lack of knowledge.Lack of resources. I was working remotely from the south end of the airport without a computer to verify my work and lack of proper lighting for verification process. Stress because of these factors plus pressure management to clear MEL.Add to the MEL FR process to visual check the skin air valve is in the full close position; flush fuselage skin.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.