Digital

Starting with the E38, hall effect sensors were used as wheel speed sensors. Their unique two wire configuration swayed from the conventional three wire variants of previous hall effect sensors.

The two wire, hall effect speed sensors receive a stabilized 8 volt power supply from the control module through one wire. The ground path for the sensor is through the second wire back to the control module.

The signal is generated by a pulse wheel affecting the voltage flow through the hall element in the sensor.

This affect creates the square wave signal with a low of .75 volts and a high of 2.5 volts. The unique feature of this hall element is its shared ground/signal wire to the control module.