Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
DTC 16, Vehicle Speed Signal Buffer Fault: Notes
Speed sensor circuit consists of a magnetic induction type sensor, a vehicle speed sensor buffer module and wiring. Gear teeth pressed on output shaft induce an alternating current in sensor. This signal is transmitted to buffer. Buffer compensates for various axle ratios and converts signal into a square wave for use by speedometer, cruise control, anti-lock brakes and PCM. Buffer sends 2 different signals to PCM.
Transmission output speed signal circuit relays transmission output speed which is used to control shift points, line pressure, TCC, DTC 24 and DTC 72. Vehicle speed signal circuit relays vehicle speed which is used to control engine operating functions and DTC 16. When DTC 24 or 72 is set, 2nd gear only at maximum line pressure will occur. DTC 16 will set when:
- Vehicle speed greater than 20 MPH.
- 1000-4400 RPM.
- Vehicle speed signal circuit is open or grounded.
- All conditions must be met for 2 seconds.
PCM will default to no cruise control or fuel cutoff.
- This tests for battery voltage at VSS buffer.
- This tests for proper ground path for vehicle speed sensor signal buffer.
- This tests for vehicle speed sensor signal buffer signal to PCM.
- This tests for a signal from VSS buffer to PCM.
NO RELATED
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:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.