Posted 5/27/2023 15:17 (#10245941 - in reply to #10245479) Subject: RE: Raven 440 speed sensor
Near Intersection of I-35 & I-90 Southern Mn.
The outside shield in the CoAx is ground. One inside wire is 5V to power the sensor, the other inner wire is the signal wire. It is normally held at 5V but the sensor can temporarily short it to ground and release it back to 5V. The system counts this as a pulse. It counts these pulses and multiplies the count by the speed meter cal. If your is counting too much then the wires are probably OK but the signal wire is bare somewhere and creates extra pluses by shorting to the ground wire. This would be very difficult to find.
Probably the best use of your time and money is to buy new or get a different style speed sensor.