We looked at a site months ago, and one door would not open all the time with a card. We could not get into the power supply cabinet since it was locked and nobody wanted to force it open. The card worked sometimes, and we double-checked security levels, etc and the controller was showing lights that it was processing the data. The reader also went from red to green when the card was presented.
Same site, new owner and we looked at another door very quickly. We were there for video, not access. Presented a card and the reader turned green but the mag would not open.
My thought is the power supply is bad, sticky relay? The power supply is probably 15+ years old.
Ideas?