Vehicle Speed Sensor (VSS) Inspection

VEHICLE SPEED SENSOR (VSS) INSPECTION [FS5A-EL]

Wave Profile Inspection
1. Inspect the power supply circuit for the VSS.
1) Disconnect the VSS connector.
2) Turn the ignition switch to ON.





3) Measure the voltage at VSS connector terminal A (wiring harness side).
^ If there is any malfunction, repair wiring harness between VSS and TCM.
Vehicle speed sensor (VSS) voltage 4.5-5.5 V
4) Turn the ignition switch off.
5) Connect the VSS connector.
2. Inspect the GND circuit for the VSS.
1) Turn the ignition switch off.





2) Measure the voltage at VSS connector terminal C (wiring harness side).
^ If there is any malfunction, repair wiring harness between VSS and TCM.
Vehicle speed sensor (VSS) voltage Below 1.0 V
3. Inspect the signal circuit for the VSS.
1) Connect the oscilloscope to the following TCM connector terminals and set it as below.
^ (+) lead: TCM terminal Z
^ (-) lead: TCM terminal M
^ Oscilloscope setting: 1 V/DIV (Y), 2.5 ms/ DIV (X), DC range
2) Start the engine.





3) Inspect wave profile when vehicle speed at 30 km/h (20 mph).
^ If there is any malfunction, perform the Visual Inspection.

Visual Inspection
1. Shift the selector lever to N position.
2. Remove the VSS.
1) Disconnect the negative battery cable.
2) Disconnect the VSS connector.
3) Remove the VSS from the transaxle case.
3. Verify that the sensor is free of any metallic shavings or particles.
^ If there is any malfunction, clean them off.
4. Inspect sensor rotor surface via VSS installation hole while rotating the front tire manually.
1. Is sensor rotor free of damage and cracks?
2. Is sensor rotor free of any metallic shavings or particles?
^ If sensor rotor is normal, replace the VSS.
^ If there is any malfunction, clean or replace the sensor rotor.