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Vehicle Speed Sensor: Testing and Inspection




CIRCUIT DESCRIPTION
The speed sensor for ABS detects the wheel speed and sends the appropriate signals to the ABS ECU. The ECU converts these signals into a 4-pulse signal and outputs it to the combination meter. After this signal is converted into a more precise rectangular waveform by the waveform shaping circuit inside the combination meter, it is then transmitted to the vane pump assembly with motor. The vane pump assembly with motor determines the vehicle speed based on the frequency of these pulse signals.




DETECTING CONDITIONS




WIRING DIAGRAM

Step 1:




Step 2:




INSPECTION PROCEDURE