Acura Integra 1998 Service Manual page 781

Wheel Speed and Modulator Control
OUTLET
VALVE
oN
OFF
INLET
VALVE
ON
OFF
MOTOR
ON
OFF
When the wheel speed drops sharply below the vehicle speed, the inlet valve closes to retain the caliper fluid pressure.
When the wheel speed drops further, the outlet valve opens momentarily to reduce the caliper fluid pressure. The pump
motor starts at this time.
As the wheel speed is restored, the inlet valve opens momentarily to increase the caliper fluid pressure.
Wheel Sensor
The four 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 signalfrequency and thereby detects the wheel speed.
rr LOW SPEED
5
GEAR PUTSER
19-29