In some cases, the factory sensor port on the bellhousing does not line up directly over the flywheel teeth. The sensor port may give a partial view of the flywheel which is offset by a gap or a machined edge. It is possible that a threaded speed sensor will not be able to sense speed from an offset flywheel.
Pacbrake recommends first installing the sensor into the port and checking if the system is able to read speed. You can check that the sensor is detecting speed by proceeding to Set and Test a Trip Speed. If setting and testing occur successfully, the sensor is able to read speed.
If the sensor cannot read speed, contact Pacbrake Support for an offset adapter (P/N: C50136) and a 3/8”-20 gear tooth speed sensor. The offset adapter is a sleeve with a 3/4”-16 external thread and a 3/8”-20 hole drilled off-center to allow the smaller sensor to be positioned directly over the offset flywheel teeth.
A more immediate solution would be to drill and tap a new sensor port in the correct position on the bell housing.