Q: Why does my M3491/INN3491 light the arrows, but the gong doesn’t sound?

A: This is usually caused by improper addressing of the M3491 unit.  If all dip switches are in the OFF position, the unit listens to travel arrow signals and will light the arrow, but never sound the gong.

1. If the unit is mounted in the hall, make sure that the binary floor address is properly set on the S1 and S2 bank of dip switches.  The bottom floor, regardless of its label, is always considered floor 1.
2. If the unit is mounted in the car, make sure that the binary floor address is set to 127 (S1, 3 – 8 and S2, 1 set to ON).