ESP
Front Wheel Speed Sensor Encoder On-Vehicle InspectionOutput 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 12V
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 (115 ohms) 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 ohm) with wheel rotation
High voltage "a":1360 to 1930 mV
Low voltage "b": 680 to 960 mV
