Home Forums General Discussion Technical Questions mph2 fire service issue

i got a duplex Schindler MPH II. Fire phase 1 and Fire Service Phase 2 passed on one elevator. but the other one i found dcb and dob were not working so i couldn't test phase 2. While troubleshooting these violations i found the phase 2 keyswitch with a loose wire. When i wired it back up I tested fire service once again. i activated phase 1 and both recalled into main landing. i later activated phase 2 in the elevator i cleared violations in and when i switch off fire service phase 2 it remained lit. unplugged the wire and it still remain lit. proceeded to switch off fire phase 1 to get one elevator running but then somehow after several runs later with no fire service activated the unit recalled into the main landing with doors open like if FS switched ON. had to bypass reset to turn off FS. it even did this when i killed power on the unit i was working on with all FS keyswitches set to OFF. don't have a clue why it was acting up this way but figured why they unplugged the wires from the dob and phase 2 keyswitch. Can somebody explain this strange scenario I just witnessed?

Apparently on a duplex mph2 when you cycle power on one car it can set the other car on fire service. Theirs a Schindler industry memo on the fix but I haven't been able to get my hand on a legible copy

If any Schindler guys out there have that document I'd love to get a copy