t
Wheel Sensors
The wheel sensors are the magnetic contactless type. As the gear pulser teeth rotate past the wheel sensor's magnetic
coil, AC current is generated. The AC frequency changes in accordance with the wheel speed. The ABS control unit
detects the wheel sensor signal frequency and thereby detects the wheel speed.
!t LOW SPEED
Wheel Speed and Modulator Control
8E!EEETqE VEJ!q!ESPEEq
5
PRESSURE
OUTLETVALVE 9p
OFF
INLETVALVE oN
OFF
MoroR I-,. ltlOFF
When the wheel speed drops sharply below the vehicle speed, the inlet valve closes and il necessary, the outlet valve
opens momentarily to reduce the caliper fluid pressure. The pump motor starts at this time. As the wheel speed is
restored, and the outlet valve closes, the inlet valve opens momentarily to increase the caliper fluid pressure.
GEAR PULSERWHEEL S€NSOR.r HIGX SPEED
19-41
