Code 24, VSS - M/T: Notes
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NOTE:
The VSS buffer is an internal part of the Digital Ratio Adapter Controller (DRAC) and the terms are used interchangeably.
Control module applies and monitors 12 volts on VSS signal circuit. Circuit is connected to VSS buffer which alternately grounds this circuit when it is receiving voltage pulses from Vehicle Speed Sensor (VSS). Scan tester reading should closely match speedometer reading.
NOTE:
Test numbers refer to test numbers on diagnostic chart.
- Checks to see if code is set as a result of a hard failure or an intermittent condition.
- This determines if VSS buffer is receiving AC signal from VSS.
- This test monitors VSS buffer voltage on VSS signal circuit. With wheels turning, pulsing voltage should be present. Voltage variation will be greater at a low speed to an average of 4-6 volts at about 20 MPH.