Camry XLE Sedan 4-Door L4-2164cc 2.2L DOHC MFI (1997)
Wheel Speed Sensor: Description and Operation
Nippondenso Type
Speed Sensor Circuit Description
PURPOSE
The Wheel Speed Sensor detects wheel speed and sends the appropriate signals to the Electronic Control Unit (ECU). These signals are used to
control the Anti-Lock Brake System (ABS) system.
OPERATION
A reluctor (wheel sensor rotor) with 48 serrations rotates with each wheel. When the wheels rotate, the teeth of the rotor interrupt a magnetic field
emitted by a permanent magnet manufactured into the wheel speed sensor. The changing magnetic field induces an AC voltage in the sensor
circuit. Since the frequency of this AC voltage changes in direct proportion to the speed of the wheel, the frequency is used by the ECU to detect
the speed of each wheel.
FAIL SAFE FUNCTION
If trouble occurs in the Speed Sensor circuit, the ECU cuts off current to the ABS Solenoid Relay and prohibits ABS control.
