Kone Kcm 831 detector edge problem

I have a car that will trip the detector edge and reopen every time it gets about 1/4 closed. the funny thing is if i access the car down and run the doors from the door operator switch, it never trips. it is the Kone edges that sit on the back edge of the car sill, and do not move with the door, they are real thin, and they plug into the AMD1 drive, and then the signal goes to the ccbn board on the car and finally to the lce board in the controller. i see the red led on the edge turn on , then it reopens, the funny thing is the led stays red until it get fully open. Am i missing something here? the thing that keeps bothering me is i can't get the unit to fail if i run it manually from the door control buttons. any ideas,

Bad leads to the detector perhaps.

The detector edge went out of alignment, happens all the time on these kone lifts.

Could also be a bit of protective film on doors, don't think I've ever seen a Kone lift with it all removed especially monos, I've had same fault & it was a piece of Sellotape that had got dusty flapping on doors,
But as denzelevator says they are very flimsy

Dave

The diodes in these edges can deteriorate with age so if alignment and cables etc are ok you may have to renew the edges

Had one doing the same thing, eneded up just replacing everything and all is well again.

Yep they are cheap enough, I take it they are formula system?
Dave