#
VEHICLE SPEED SENSOR (VSS) INSPECTION [FN4A-EL]

BME051719200211

## Visual Inspection

1. Remove the VSS. (See VEHICLE SPEED SENSOR (VSS) REMOVAL/INSTALLATION [FN4A-EL].)

2. Verify that the sensor is free of any metallic shavings or particles.

  • If there is any malfunction, clean them off.

3. Install the VSS. (See VEHICLE SPEED SENSOR (VSS) REMOVAL/INSTALLATION [FN4A-EL].)

## Wave Profile Inspection

1. Remove the PCM. (See INTAKE-AIR SYSTEM REMOVAL/INSTALLATION [L3].)

2. Connect the WDS or equivalent to DLC-2.

3. Connect oscilloscope test leads to the following PCM connector terminals.

  • (+) lead: PCM terminal 3C
  • (-) lead: PCM terminal 2AC

4. Start the engine.

5. Monitor the VSS PID.

6. Inspect the wave profile.

  • PCM terminal: 3C (+)-2AC (-)
  • Oscilloscope setting: 1 V/DIV (Y), 2.5 ms/DIV (X), DC range
  • Vehicle condition: drive the vehicle at 32 km/h {20 mph}

  - If there is any malfunction, perform the "Open Circuit Inspection" or "Short Circuit Inspection"

## Power Supply Voltage Inspection

1. Disconnect the VSS connector.

2. Turn the ignition switch to the ON position.

3. Measure the voltage at VSS terminal B.

Specification

  4.5-5.5 V

  • If voltage is normal, go to Open Circuit Inspection and Short Circuit Inspection.
  • If there is any malfunction, repair the wiring harness between the VSS and the PCM.

## Open Circuit Inspection

1. Inspect the following for open circuit.

  • Power circuit (VSS terminal A to main relay)
  • Ground circuit (VSS terminal C to GND)
  • If an open circuit or short circuit is found, repair the malfunctioning wiring harness.
  • If there are no open or short circuit, perform the sensor rotor inspection.

## Short Circuit Inspection

1. Inspect the following for short circuit.

  • Power circuit (VSS terminal A to main relay)
  • If an open circuit or short circuit is found, repair the malfunctioning wiring harness.
  • If there are no open or short circuit, perform the sensor rotor inspection.

## Sensor Rotor Inspection

1. Remove the VSS. (See VEHICLE SPEED SENSOR (VSS) REMOVAL/INSTALLATION [FN4A-EL].)

2. Shift the selector lever to the N position.

3. Inspect the sensor rotor surface via VSS installation hole while rotating the front tire manually.

  (1) Is the sensor rotor free of damage and cracks?
  (2) Is the 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.