How does the ABS sensor determine wheel speed?
The ECU uses the ABS sensor signal in two ways. When the wheel rotates fast enough for the ABS sensor signal to become larger than a certain threshold, the ECU determines the wheel speed using the rising and falling edges of the signal.
What are the different types of ABS sensors?
Sensor information Type: ABS sensor inductive Power supply: – Signal type: Amplitude and frequency varying Signal level: 0.4 V to 8 V
Why does the Hall effect ABS sensor have a low frequency?
Channel 1 (red) shows the signal voltage of the Hall effect ABS sensor and channel 2 (yellow) the power supply. The signal starts with low frequency because the wheel rotates slowly. In the middle of the measurement the frequency is high due to higher speed of the rotation.
What does no signal mean on wheel speed sensor?
No signal means a bad sensor or wiring fault. NOTE: Active wheel speed sensors cannot be accurately tested by measuring resistance across the sensor’s terminals. You have to look for a good return signal from the sensor while it is receiving power from the control module or a 12-volt battery, and while the wheel is turning.
What happens if you have a bad ABS sensor?
Loss of anti-lock brakes: Usually, the ABS computer will disable the ABS system if it detects a problem with a wheel speed sensor or its circuit. Loss of stability and traction control: If it detects a bad wheel speed sensor, the ABS computer will usually disable the stability and traction control systems, as well.
What kind of wheel speed sensor does ABS use?
Hall-effect sensors are often referred to as “active wheel speed sensors” and are more accurate than the magnetic type. On most vehicles made in the last couple decades, there are four wheel speed sensors — one at each wheel. Signals from these sensors are used by the ABS computer to determine how quickly the car is slowing.
No signal means a bad sensor or wiring fault. NOTE: Active wheel speed sensors cannot be accurately tested by measuring resistance across the sensor’s terminals. You have to look for a good return signal from the sensor while it is receiving power from the control module or a 12-volt battery, and while the wheel is turning.
What should range be on inductive ABS sensor?
When the wheel is turned by hand, the signal voltage is lower than that of a driven car. When the sensor is measured on a driving car, the range should set to 8 V with the range button .