Got hung up on a weird door lock fault in a 90s Otis unit for almost a full shift

The call was for intermittent door lock failure on the 5th floor. I checked the lock cam, the contacts, the wiring back to the controller, everything tested fine. The issue only popped up maybe once every 20 cycles. Turned out the problem was a tiny, almost invisible crack in the solder joint on the lock relay board inside the machine room controller. It would lose connection when the car passed a certain point and the frame flexed just a bit. Took me 7 hours to finally spot it with a magnifying glass while wiggling the board. Anyone else ever get fooled by a board fault that looked perfect?

2 comments

2 Comments

evan1515d ago

Ugh, I have to completely disagree here. Spending a whole shift on a tiny solder crack is a total waste of time and company money. You should have just swapped out the entire relay board the second you suspected it. That's basic troubleshooting, replace the likely bad part and get the unit running. Now you have a delayed repair and a board you still can't fully trust.

parker_bell5d ago

Nah, that's how you miss the real problem.