Operation CHARM: Car repair manuals for everyone.

ABS

Front and Rear Wheel Speed Sensor On-Vehicle Inspection

Output Voltage Inspection
1. Disconnect negative (-) cable from battery.
2. Hoist vehicle a little.
3. Disconnect wheel speed sensor connector.
4. Set up measuring device as shown in figure, the resistance to 115 ohms and the power supply voltage to 12 V.

CAUTION: Incorrect voltage and/or wrong connection cause damage to wheel speed sensor.








5. Measure voltage at resistance without wheel rotation. If voltage is out of specification, check sensor, mating encoder and their installation conditions.

Voltage at the resistance (115 ohms) without wheel rotation: 680 - 960 mV

6. Measure voltage at resistance with wheel rotation and confirm voltage alternately changes between high and low voltages. If voltage does not change with wheel rotation, check sensor, mating encoder and their installation conditions.

Voltage at the resistance (115Q) with wheel rotation:
High voltage "a": 1360 - 1930 mV
Low voltage "b": 680 - 960 mV





Reference
When using oscilloscope for this check, check if peak-to-peak voltage and waveform meet specification.

Peak-to-peak voltage at the resistance (115 ohms) with wheel rotation
High voltage "a": 1360 to 1930 mV
Low voltage "b": 680 to 960 mV