Vehicle Speed Sensor Signal: Testing and Inspection

Vehicle Speed Signal Circuit Troubleshooting

1. Raise the vehicle, and make sure it is securely supported.




2. Disconnect the 3P connector from the vehicle speed sensor (VSS).




3. Check for continuity between the VSS 3P connector No.3 terminal and body ground.
Is there continuity?

YES - Go to step 4.
NO - Repair open in the BRN/YEL wire between the VSS and G101.

4. Disconnect the throttle position (TP) sensor 3P connector.
5. Turn the ignition switch ON (II).




6. Measure voltage between the VSS 3P connector No. 1 terminal and body ground.
Is there approx. 5 V?

YES - Go to step 7.
NO - Repair short in the YEL/BLU wire between the VSS and ECM, or the throttle position (TP) sensor.




7. Measure voltage between the VSS 3P connector No.2 terminal and body ground.
Is there approx. 5 V?

YES - Go to step 8.
NO - Repair short to ground or open in the BLU/WHT wire between the VSS and ECM or the gauge assembly.

8. Reconnect the 3P connector at the VSS.
9. Put the car in neutral with the ignition switch ON (II).
10. Slowly rotate the propeller shaft.




11. Measure voltage between the gauge assembly connector C (20P) No.3 terminal and body ground.
Does voltage pulse from 0 to approx. 5 V?

YES - Replace the printed circuit board.
NO - Replace the VSS.