VEHICLE SPEED SENSOR (VSS) INSPECTION [FN4A-EL]
id051701801400
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 PCM.
-
Vehicle speed sensor (VSS) voltage
-
B+
- (4) Turn the ignition switch off.
- (5) Connect the VSS connector.
2. Inspect the ground 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 PCM.
-
Vehicle speed sensor (VSS) voltage
-
Below 1.0 V
3. Inspect the signal circuit for the VSS.
- (1) Connect the oscilloscope to the following PCM connector terminals and set it as below.
-
-
• (+) lead: PCM terminal 1AX
• (–) lead: battery negative terminal
• Oscilloscope setting: 1 V/DIV (Y), 2 ms/DIV (X), DC range
- (2) Start the engine.
- (3) Inspect wave profile when vehicle speed at 30 km/h {20mph}.
-
-
• If there is any malfunction, perform the “Visual Inspection”.(See
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 there is any malfunction, clean or replace the sensor rotor.