Code 24, VSS - M/T: Notes

1995 Chevrolet Forward Control 4.3 Z, AutomaticSECTION Notes
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.
  1. Checks to see if code is set as a result of a hard failure or an intermittent condition.
  2. This determines if VSS buffer is receiving AC signal from VSS.
  3. 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.
RENDER: 1.0x

NO RELATED

Recommended Tools & Savings

Use the Manual With the Right Hardware

Pair factory procedures with proven DIY tools so the instructions are easier to execute.

Affiliate disclosure: We may earn a commission at no extra cost to you.

When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • β€’ You smell fuel, burning insulation, or see smoke.
  • β€’ Brakes feel soft, pull hard to one side, or make grinding noises.
  • β€’ The engine overheats, stalls repeatedly, or misfires under load.
  • β€’ You are missing required tools, torque specs, or safe lifting equipment.
  • β€’ You are not confident in the next step or safety outcome.