On-Vehicle Inspection

WARNING: This page is about a different car, the 2009 Mazda 6. However, it is still accessible from the selected car via links, so may be relevant.

Inspect the power supply circuit for the VSS.
1. Remove the aerodynamic under cover NO. 2. (See AERODYNAMIC UNDER COVER NO. 2 REMOVAL/INSTALLATION .)
2. Disconnect the VSS connector.
3. Switch the ignition to ON (engine off).
  
  Fig 1: Locating Vehicle Speed Sensor
  Courtesy of MAZDA MOTORS CORP.
4. Measure the voltage at VSS connector terminal A (harness-side).
  - If there is any malfunction, repair wiring harness between VSS and TCM.
    VSS specification 4.5-5.5 V
    
    Fig 2: Identifying Vehicle Speed Sensor Connector (Harness Side)
    Courtesy of MAZDA MOTORS CORP.
5. Switch the ignition to off.
6. Connect the VSS connector.
Inspect the GND circuit for the VSS.
1. Switch the ignition to off.
2. Measure the voltage at intermediate sensor connector terminal C (harness-side).
  - If there is any malfunction, repair wiring harness between intermediate sensor and TCM.
    Intermediate sensor specification Below 1.0 V
    
    Fig 3: Identifying Vehicle Speed Sensor Connector (Harness Side)
    Courtesy of MAZDA MOTORS CORP.
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 2P
  - (-) lead: battery negative terminal
  - Oscilloscope setting: 1 V/DIV (Y), 2 ms/DIV (X), DC range
2. Start the engine.
3. Measure the wave form when vehicle speed at 30 km/h {19 mph}.
  - If there is any malfunction, replace the VSS. (See VEHICLE SPEED SENSOR (VSS) REMOVAL/INSTALLATION [FS5A-EL] .)
    
    Fig 4: View Of Waveform Graph
    Courtesy of MAZDA MOTORS CORP.