Home Forums General Discussion Technical Questions Otis gen2 mrl continually faulting out

For weeks now I have had an Otis gen2 mrl continually fault out on the bottom floor with doors shut and a 2907 ucm fault. Today upon arrival I also had a 2848 bds fault with it. Funny thing to is every once in a while when the 2907 takes place it also triggers fire service on that specific car (it’s a duplex). Today I had to reset fire svc as well.

So far I have checked/adjusted brake switch, cleaned brake switch, checked bottom floor interlock/contacts, checked the cps and cleaned, adjusted clutch to make sure rollers not actuating upon movement

Still, the issue persists. Any ideas?

2848 points to your bottom door lock. Any other faults in M-2-2-2?

Right, that’s why I checked the interlock/contacts but it looks perfect. And no, just generic ones

Bump

Bumpppp

Will need for information, on automatic we need a list of your I/Os etc.

Need to find the fault causing the shutdown list all mcss ocss and drive

2907 is pointing to a low speed UCM event. The controller is seeing the car move more than 6” from a DZ while the doors show open.

I would expect to see some other faults with this fault. How old is this car? How do the belts and sheaves look?

The Fire service issue could be a clue to something also but I’d assume that was the building trying to recall the cars? You can check OCSS logs of the other car to confirm that.

If your confident it’s not a door issue, you can try making the car park at a different floor or even remove the problem floor from the CUDE mask temporarily to see if your issue moves or goes away.

Interesting issue. Since it’s happening at the bottom floor with doors closed and intermittently triggering UCM, could it be a slight movement being detected from brake slip or feedback mismatch?

Also wondering if encoder/CPS signal noise or grounding could be playing a role—especially since it’s occasionally tying into fire service.

Have you checked the brake pickup/drop timing or monitored the feedback signals when the fault occurs?

It hasn’t happened again since last week and I cleared the faults/ram. Do you still want info? If so what?

Also car has been running since last week after I cleaned the flag for cps



Car is 4 years old I think. Belts and sheave are good (belts were done last year actually). The other car next to it doesn’t go into fire service.

I can try that. What exactly is a cude mask? What’s the input on the blue tool to do what you’re saying?

Also, I’m 99% sure it’s not a door issue. No need interlock makes contact well and clutch doesn’t seem to hit it improperly on the way down/up

Also car has been running since last week after I cleaned the flag for cps



Yes I have adjusted the brake drop/pick and also cleaned out the contacts. I have monitored them in the menu which shows 0 0 0 0 etc for brake pick (I forget the button combo to get there). It seems to be functioning properly.

I have checked the cps and it seems clean/functioning properly. Any diagnostic steps you suggest to go further in that regard?

Also any diagnostic steps to go further with the encoder? I haven’t checked that

Also car has been running since last week after I cleaned the flag for cps

I’m not sure what you are referencing about the “flag for cps”?

If it’s not faulted out, I’d just check the logs from time to time at this point. There really shouldn’t be any MCSS faults logged normally. OCSS might get some DTC’s from people holding the doors etc. but for the most part the Gen2 shouldn’t be logging faults.

I wouldn’t be looking at the encoder at this time as you’re not seeing any faults related to it.

What is pickup roller spacing