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Vehicle Speed Sensor Signal Buffer: Description and Operation

DESCRIPTION
The vehicle speed buffer recieves voltage pulses from the Vehicle speed Sensor (VSS), and uses them to close two solid state switches within the buffer. Each sensor pulse closes these switches once. The output terminals are switched to ground at a rate that indicates the speed of the vehicle. The output switches in the vehicle speed buffer are solid state switches, not mechanical ones. Self-powered test lights or ohmmeters should NOT be used to test them. Do NOT measure the resistance at the outputs of the buffer.